FIVE  COLLEGE 
POSITORY 


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HORTICULTURE, 

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J.  E.  TESCHEMACHER. 


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AGRICULTURAL 

COLLEGE 


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Teschemacher 

Elements  of 
Horticulture. 


OCT  17 


w- 


\\  V  V  ^A 


CONCISE    APPLICATION 


PRINCIPLES   OF    STRUCTURAL    BOTANY 


HORTICULTURE, 


CHIEFLY    EXTRACTED     FROM    THE    WORKS    OF    LINDLEY, 
KNIGHT,    HERBERT,     AND     OTHERS,     WITH    ADDI- 
TIONS AND  ADAPTATIONS    TO    THIS    CLIMATE. 


By  J.  E.  TESCHEMACHER. 


BOSTON: 

CHARLES  C,  LITTLE  AND  JAMES  BEOWN. 


MDCCCXL. 


432, 


Entered  according  to  Act  of  Congress,  in  the  year  1840,  by 
Chari.es  C.  Little  and  James  Brown,  in  the  Clerk's  Office  of 
the  District  Court  of  the  District  of  Massachusetts. 


BO  STON: 

FKEEMAN    AND    BOLLES,    PRINTERS, 

VVASHINi;iO>    SIllEET. 


PREFACE. 


The  combination  of  practical  skill  and  experi- 
ence with  scientific  investigation  and  knowledge, 
the  former  giving  results,  the  latter  affording  rea- 
sons for  these  results,  and  sketching  the  outlines 
of  farther  experiments,  has  always  appeared  the 
surest  ground  of  obtaining  information  of  the 
greatest  value  on  all  subjects  of  natural  science. 

A  concise  and  simple  explanation  of  some  of  the 
prominent  facts  and  laws  of  vegetable  physiology  so 
that  they  might  become  known  to,  and  guide  those 
agriculturists  and  horticulturists,  whose  time  is  too 
much  occupied  to  permit  them  to  go  into  the  detail 
of  the  reasoning  involved  in  the  numerous  experi- 
ments scattered  through  many  volumes  and  pe- 
riodicals, must  be  of  advantage. 

The  valuable  experiments  of  Knight,  the  works 
of  Lindley,  Decandolle,  Herbert  and  others,  the 
Compilations  of  Loudon,  and  some  of  the  results 
of  the  extraordinary  attention  paid  within  the  last 


IV  PREFACE. 

fifteen  years  throughout  Europe  to  the  laws  and 
operations  of  vegetable  life,  added  to  my  own  ex- 
perience and  study  of  this  subject,  compose  the 
basis  on  which  this  little  publication  is  founded. 

The  subject  of  Manure,  and  the  properties  of 
soils,  do  not  strictly  belong  to  structural  botany, 
but  the  few  details  inserted  regarding  them  cannot 
be  thought  misplaced. 

The  diseases  of  Plants  must  be  left  to  the  Ento- 
mologist as  far  as  the  insects  which  infest  them 
are  concerned,  and  to  the  Crypi  prnist  as  respects 
the  injuries  inflicted  by  fungi  lichens  and  mosses. 
Nor  are  there  any  channels  infb  which  the  labors 
of  those  who  are  devoted  to  such  branches,  can  be 
diverted  with  more  interest  to  themselves  or  value 
to  mankind. 

It  cannot  be  denied  that  many  of  the  advanta- 
geous practices  in  Horticulture  and  Agriculture 
have  been  discovered  by  the  mere  practical  man, 
without  any  deductions  from  science,  or  the  laws 
of  vegetation.  Yet  it  is  probable  that  had  the 
knowledge  of  these  laws  been  earlier  and  more 
widely  disseminated,  these  advantages  would  have 
been  sooner  known  and  more  generally  diffused 
than  they  are  at  present.     Many  are  disinclined  to 


PREFACE.  V 

adopt  a  new  course,  and  reject  the  old  one  to  which 
they  have  been  long  attached,  without  some  very 
palpable  and  sufficient  reasons  for  the  change. 
But  one  improvement  introduced  and  properly 
accounted  for,  paves  the  way  for  others,  and  the 
mind  is  prepared  to  inquire.  In  this  country, 
particularly,  such  a  frame  of  mind  is  prevalent, 
and  has  produced  very  important  results  in  agri- 
culture ;  it  will  do  the  same  in  horticulture,  now 
comparatively  in  its  infancy. 

It  seemed,  therefore,  that  the  separation  of  a 
few  of  the  principal  facts  concerning  the  structure 
and  parts  of  vegetables  from  the  other  masses  of 
botanical  knowledge  with  which  they  are  usually 
published,  and  their  application  to  the  practice  of 
horticulture  could  not  fail  to  be  favorably  received 
in  this  community. 

A  complete  treatise  on  these  subjects  cannot  be 
expected  in  a  work  of  this  nature,  but  if  the  facts 
and  reasoning  give  rise  to  new  experiments,  and 
produce  results  favorable  to  the  progress  of  Horti- 
culture or  Agriculture,  the  object  of  the  publication 
will  be  completely  answered, 

1* 


APPLICATION 


STRUCTURAL    BOTANY 


HORTICULTURE. 


General  Nature  of  Plants. 

Horticulture  is  the  application  of  the  arts 
of  cultivation,  to  the  improvement  for  the  use 
or  delight  of  man,  as  well  as  to  the  domestica- 
tion, of  the  vegetable  kingdom. 

Agriculture  and  Arboriculture  are  included 
in  this  definition. 

Plants  are  organized  bodies,  composed  of  a 
substance  called  Tissue,  which  is  so  delicate 
and  thin  as  to  permit  fluids  and  gases  to  pass 
through. 

This  Tissue  exists  either  in  the  form  of  mi- 


8       GENERAL  NATURE  OF  PLANTS. 

nute  bladders  called  cells,  which  are  filled  with 
juices  and  lie  close  to  each  other,  leaving  how- 
ever intermediate  passages  where  they  do  not 
touch  —  this  is  Cellular  tissue ;  or  in  slender 
tubes  called  woody  fibre  which  are  closed  at 
each  end,  conical,  and  placed  side  by  side. 

Or  in  a  fibre  either  rolled  up  spirally  like  a 
wire  spring,  or  forming  long  cylindrical  vessels 
placed  end  to  end,  which  finally  become  con- 
tinuous and  lie  close  to  each  other ;  this  is  called 
vascular  tissue  —  from  vas  a  vessel. 

Cellular  tissue  when  just  formed  is  very  lax 
or  coheres  loosely  and  possesses  great  powers 
of  absorption. 

Late  microscopic  discoveries  have  enabled 
botanists  to  distinguish  several  varieties  of  Cel- 
lular tissue.  Even  their  names,  however, 
would  be  misplaced  here. 

It  constitutes  the  soft  and  brittle  parts  of 
plants,  as  pith,  pulp,  the  soft  part  between  the 
veins  of  leaves,  the  tender  parts  of  the  flower, 
fruit,  &c. 

Succulent  plants,  as  the  Cactus,  have  an  ex- 
cessive development  of  this  tissue. 

It  may  be  considered  the  most  essential  kind 
of  tissue,  because,  while  no  plants  exist  without 
it,  many  are  composed  of  nothing  else. 


GENERAL  NATURE  OF  PLANTS.        \) 

Woody  Fibre  is  what  causes  stiffness  and 
tenacity  in  certain  parts  of  plants ;  hence  it  is 
found  in  the  veins  of  leaves,  and  in  bark,  and 
it  constitutes  the  principal  part  of  the  wood. 

The  most  remarkable  form  of  vascular  tissue 
is  the  Spiral  vessel,  which  has  the  power  of 
unrolling  with  elasticity  when  stretched. 

Other  kinds  of  vascular  tissue  are  incapable 
of  unrolling,  but  break  when  stretched. 

Spiral  vessels  are  not  found  in  the  wood  or 
bark,  and  rarely  in  the  roots  of  plants. 

Vascular  tissue  of  other  kinds  is  confined  to 
the  root,  stem,  veins  of  leaves,  petals,  and  other 
parts  composed  of  leaves.  It  is  not  found  in 
bark. 

The  common  office  of  the  tissue  is  to  convey 
fluid  or  air,  and  to  act  as  the  receptacle  of 
secretions. 

The  cells  of  Cellular  tissue  convey  fluids  in 
all  directions  through  their  sides,  and  absorb 
with  great  rapidity ;  when  placed  in  contact 
with  cells  of  the  same  species  they  join  together 
and  adhere  —  as  is  exemplified  in  budding  and 
grafting  —  the  cells  adhere,  then  form  Woody 
fibre  —  but  cells  of  different  or  widely  related 
species  will  not  form  a  junction. 

This  is  the  operation  of  grafting  or  budding, 


10      GENERAL  NATURE  OF  PLANTS. 

in  which,  however,  the  similar  parts  of  the 
stock  and  scion  must  be  brought  into  close  con- 
tact, and  kept  so  for  some  time,  and  this  must 
be  done  during  the  growing  season. 

Woody  fibre  conveys  fluid  in  the  direction 
of  its  length,  gives  stiffness  and  flexibility  to  the 
general  system,  and  acts  as  a  protection  to  spiral 
and  other  delicate  vessels. 

Spiral  vessels  convey  oxygenated  air. 

Other  vessels  probably  conduct  fluid  when 
young,  and  air  when  old. 

As  the  bodies  of  which  all  tissue  is  composed 
are  perfectly  simple,  unbranched,  and  regular 
in  figure,  having,  when  elongated,  their  two 
extremities  exactly  alike,  they  are  more  or  less 
capable  of  conveying  gaseous  matter  or  fluids 
in  any  direction ;  and,  consequently,  a  current 
may  be  reversed  in  them  without  inconven- 
ience :  hence,  inverted  cuttings  or  stems  will 
grow. 

All  parts  of  plants  are  composed  of  tissue, 
whether  they  be  soft,  as  pulp  ;  or  hard,  as  the 
bony  stone  of  a  Peach. 

With  regard  to  Horticultural  operations,  the 
parts  of  plants  should  be  considered  under  the 
heads  of  Root,  Stem,  Leaf -buds,  Leaves,  Flow- 
ers, Stamens  and  Pistils,  Frmt,  and  Seed. 


11 


Root. 

The  Root  is  the  part  that  strikes  into  the 
earth  when  a  seed  begins  to  grow,  and  which 
afterwards  continues  to  lengthen  beneath  the 
soil.  But  some  roots  do  not  require  the  soil, 
and  draw  their  nutriment  from  the  atmosphere, 
as  the  Ivy,  Air-Plants,  &c.,  others  live  on  the 
juices  of  trees,  as  the  Misletoe,  &c.,  they  are 
called  parasitical. 

It  is  distinguished  from  the  stem  by  the 
absence  of  leaves  in  any  state,  of  regular  leaf- 
buds  ;  of  evaporating  pores,  or  stomata ;  and 
of  pith  in  Exogenous  plants. 

Therefore,  such  underground  bodies  as  those 
called  Tuber  of  the  Potato  ;  Bulb  of  the  Onion ; 
and  solid  Bulb  or  Cormus  of  the  Crocus,  are 
not  roots. 

The  office  of  the  root  is  to  absorb  food,  in  a 
fluid  or  gaseous  state  ;  and  also  to  fix  the  plant 
in  the  soil,  or  to  some  firm  support. 

The  latter  office  is  essential  to  the  certain 
and  regular  performance  of  the  former. 

It  is  not  by  their  surface  only  that  roots  ab- 
sorb food;  it  is  chiefly  by  their  young  and 
newly  formed  extremities,  called  Spongioles. 


12  ROOT. 

Hence  the  preservation  of  the  spongioles  in 
an  uninjured  state  is  essential  to  the  removal  of 
a  plant  from  one  place  to  another,  and  care 
should  be  taken  to  preserve  even  the  smallest 
fibres  of  the  roots  uninjured. 

A  Spongiole  consists  of  very  young  vascular 
tissue,  surrounded  by  very  young  cellular  sub- 
stance. 

It  is  therefore  one  of  the  most  delicate  parts 
of  plants,  and  the  most  easily  injured. 

Hence  whatever  is  known  to  produce  any 
injurious  action  upon  leaves  or  stems,  such  as 
certain  gases  and  mineral  or  vegetable  poisons, 
will  produce  a  much  more  fatal  effect  upon  the 
spongioles. 

These  spongioles  have  no  powder  of  selecting 
their  food,  but  will  absorb  whatever  the  earth 
or  air  may  contain,  which  is  sufficiently  fluid 
to  pass  through  the  sides  of  their  tissue. 

So  that  if  the  spongioles  are  developed  in  a 
soil  which  is  of  an  unsuitable  nature,  as  they 
will  still  continue  to  absorb,  they  cannot  fail  to 
introduce  matter  which  will  prove  either  in- 
jurious or  fatal  to  life,  according  to  its  intensity. 

This  may  often  explain  why  trees  suddenly 
become  unhealthy,  without  any  external  appa- 
rent cause. 


ROOT.  13 

Plants  have  the  power  of  replacing  spongioles 
by  the  formation  of  new  ones ;  so  that  an  in- 
dividual is  not  destroyed  by  their  loss. 

But  this  power  depends  upon  the  coopera- 
tion of  the  atmosphere,  and  upon  the  special 
vital  powers  of  the  species. 

If  the  atmosphere  is  so  humid  as  to  hinder 
evaporation  from  the  leaves,  spongioles  will 
have  time  to  form  anew  ;  but  if  the  atmosphere 
is  dry,  the  loss  by  evaporation  will  be  so  much 
greater  than  can  be  supplied  by  the  injured 
roots,  that  the  whole  plant  will  be  emptied  of 
fluid  before  the  new  spongioles  can  form,  and 
death  will  ensue. 

This  is  the  key  to  the  operations  of  trans- 
plantation and  propagation  by  cuttings  scions 
and  buds. 

As  roots  are  destitue  of  leaf-buds,  and  as 
leaf-buds  are  essential  to  the  multiplication  of 
an  individual,  it  should  follow  that  roots  can 
never  be  employed  for  the  purpose  of  multipli- 
cation. 

Nevertheless,  roots  have,  occasionally,  the 
power  of  generating  leaf-buds,  which  being 
latent,  and  not  according  to  the  usual  operations 
of  nature,  are  called  adventitious;  and  when 
this  is  the  case,  they  may  be  employed  for  the 
2 


14 


ROOT. 


purpose  of  multiplication ;  as  those  of  Cydonia 
Japonica,  &c. 

The  cause  of  this  power  existing  in  some 
species,  and  not  in  others,  is  unknown. 

It  is  therefore  a  power  that  can  never  be 
calculated  upon ;  and  whose  existence  is  only 
to  be  discovered  by  accident. 

The  immediate  cause  of  the  formation  of 
roots  is  at  present  involved  in  obscurity,  but  the 
fact  is  well  known  that  some  plants  when  pro- 
pagating by  cuttings  produce  roots  with  much 
more  facility  and  in  a  shorter  time  than  others. 

Darkness,  moisture,  and  perfect  rest,  seem 
necessary  for  this  purpose  —  as  well  as  a  down- 
ward circulation  of  the  sap,  which  is  effected 
by  the  action  of  the  leaves  on  the  upper  part 
of  the  stem  —  nor  can  the  roots  exist  by  them- 
selves without  the  leaves  to  create  the  action 
of  drawing  up  the  juices  they  absorb  —  therefore 
a  cutting  without  leaves  will  soon  perish. 

Although  roots  are  generated  under  gound, 
and  sometimes  at  considerable  depths,  yet  ac- 
cess to  a  certain  quantity  of  atmospheric  air 
appears  indispensable  to  the  healthy  execution 
of  their  functions.  This  is  constantly  exem- 
pUfied  in  plants  growing  in  the  earth  at  the  back 
of  an  ill-ventilated  forcing  house,  where  the 


ROOT.  15 

roots  have  no  means  of  finding  their  way  into 
the  earth  on  the  outside  of  the  house. 

The  spongioles  and  newly  formed  parts  of 
the  root  contain  considerable  nitrogen,  a  sup- 
ply of  this  gas  therefore  seems  necessary  to 
their  health.  Manure  which  contains  nitrogen 
in  abundance  must  therefore  be  of  consequence 
to  them.  It  has  lately  been  asserted  that  those 
seeds  which  contain  most  nitrogen  vegetate  the 
earliest. 

It  is  supposed  by  some  that  the  introduction 
of  oxygen  into  their  system  is  as  indispensable 
to  them  as  to  animals. 

It  seems  more  probable  that  the^  oxygen  of 
the  atmosphere,  combining  with  a  certain  quan- 
tity of  carbon,  forms  carbonic  acid,  which  they 
absorb  and  feed  upon. 

It  is  at  least  certain  that  the  exclusion  of  air 
from  the  roots  will  always  induce  an  unhealthy 
condition,  or  even  death  itself.  This  may  be 
one  of  the  reasons  why  stiff,  clayey,  tenacious 
soils  are  so  seldom  suited  to  the  purposes  of  the 
cultivator,  until  their  adhesiveness  has  been 
destroyed  by  the  addition  of  other  matter,  such 
as  sand  or  manure. 

After  the  juices  have  circulated  through  a 
plant  and  performed  their  destined  offices,  what 


16 


ROOT. 


remains  unfit  for  its  further  nourishment  re- 
turns to  the  spongioles,  is  by  them  thrown  ofi' — 
this  substance  so  thrown  off  is  unsuitable  and 
even  poisonous  to  this  species  of  plant,  but  is 
not  so  to  other  species ;  it  may  even  be  suitable 
to  them. 

Hence  soil  may  be  rendered  impure,  (or,  as 
we  inaccurately  say,  worn  out)  for  one  species, 
which  will  not  be  impure  for  others. 

This  is  the  true  key  of  the  theory  of  rotation 
of  crops. 

This  also  may  serve  to  explain  in  part  why 
light  soil  is  indispensable  to  so  many  plants, 
and  heavy  or  tenacious  soil  suitable  to  so  few : 
for  in  the  former  case  the  spongioles  will  meet 
with  little  resistance  to  their  elongation,  and 
will  consequently  be  continually  quitting  the 
place  where  their  excrementitious  matter  is  de- 
posited ;  while,  in  the  latter  case,  the  reverse 
will  occur. 

It  will  also  be  one  of  the  reasons  why  an 
orchard  planted  too  thickly  of  the  same  trees 
cannot  thrive,  the  trees  by  their  roots  soon 
absorb  all  the  nutriment  from  the  earth,  and 
only  those  on  the  borders  can  send  out  their 
roots  to  a  distance  for  fresh  juices,  those  in  the 
centre  have  little  else  to  feed  on  but  the  sub- 


ROOT.  17 

Stance  thus  cast  off  by  themselves  and  by  the 
otlicrs  around.  And  why  young  apple  trees 
planted  on  the  site  of  an  old  apple  orchard 
cannot  thrive,  the  earth  is  full  of  the  poisonous 
matter  thrown  off  by  the  roots  of  the  old  trees ; 
but  probably  young  cherry  or  peach  trees 
would  succeed.  Likewise  it  accounts  for  the 
natural  rotation  of  trees  which  has  been  dis- 
covered to  exist  in  the  ancient  forests  of  this 
part  of  the  globe ;  for  the  necessity  of  repot- 
ting plants  grown  in  green-houses  every  one 
or  two  years,  and  for  m.any  other  circumstances 
in  horticulture  for  which  hitherto  sufficient 
reasons  had  not  been  given. 

Much  of  the  healthy  action  of  the  root  de- 
pends on  the  warmth  and  moisture  of  the  soil. 
A  late  German  writer,  Mr.  Writgen,  has  made  it 
appear  probable  that  much  more  depends  on 
this  than  on  the  geological  nature  or  chemical 
state  of  the  soil,  and  when  it  is  considered  that 
the  salts  usually  found  in  the  earth  are  more 
readily  soluble  in  a  warm  moisture  than  in  a 
cold  one,  and  also  that  heat  is  favorable  to 
decomposition  and  the  production  of  gases  —  it 
seems  likely  there  is  truth  in  this  position. 

During  the  summer  in  the  temperate  parts  of 
Europe,  the  earth  at  one  and  two  feet  depth  is 
2* 


18  STEM. 

one  to  one  and  a  half  degrees  higher  in  tem- 
perature than  the  atmosphere,  but  in  tropical 
climates  the  earth  is  many  degrees  hotter. 
The  system  of  applying  bottom  heat  to  accele- 
rate the  junction  of  the  parts  of  plants  that  have 
been  grafted,  budded,  or  inarched,  is  successful 
from  its  exciting  the  healthy  and  rapid  action 
of  the  roots  in  absorbing  juices  and  supplying 
them  in  abundance  to  the  stock. 

The  root  is  never  entirely  dormant  except 
when  frozen ;  during  the  winter  it  is  slowly  col- 
lecting juices  for  the  supply  of  the  spring; 
where  the  period  of  rest  or  winter  is  long,  the 
store  of  juices  is  large,  and  vegetation  in  the 
spring  is  rapid  and  luxuriant.  This  accounts  for 
the  quick  growth  in  northern  climates  where 
plants  commence  vegetation  and  mature  their 
fruit  in  the  short  space  of  three  months. 

Stem. 

The  stem  is  that  part  of  a  plant  which  is 
developed  above-ground,  and  which  took  an 
upward  direction  at  the  period  of  germination 
of  the  seed. 

It  consists  of  a  woody  axis,  covered  by  bark 
having  pores  on  its  surface,  bearing  leaves  with 


STEM.  19 

leaf-buds  in  their  axils,  and  producing  flowers 
and  fruit. 

The  points  where  leaves  are  borne  are  called 
Nodi,  knots ;  the  spaces  between  the  leaves  are 
Liternodia,  Internodes. 

The  more  erect  a  stem  grows,  the  more 
vigorous  it  is;  and  the  more  it  deviates  from 
this  direction  to  a  horizontal  or  pendulous  posi- 
tion, the  less  is  it  vigorous. 

Some  stems  are  developed  under  ground, 
such  as  the  Tubers  of  the  Potato  and  the  Cor- 
mus  of  the  Crocus,  but  they  are  known  from 
roots  by  the  presence  of  leaves,  and  regular 
leaf-buds  upon  their  surface,  as  the  shoots  from 
the  eye  of  the  potato. 

Stems  increase  in  diameter  in  two  ways. 

Either  by  the  addition  of  new  matter  to  the 
outside  of  the  wood  and  the  inside  of  the  bark ; 
when  they  are  Exogenous ;  ex.  Oak. 

Or  by  the  addition  of  new  matter  to  their  in- 
side; when  they  are  Endogenous ;  ex.  Cane. 
Palm. 

In  Exogenous  stems,  the  central  portion, 
which  is  harder  and  darker  than  that  at  the  cir- 
cumference, is  called  Heart-wood;  while  the 
exterior,  which  is  softer  and  lighter,  is  called 
Alhurnum  or  Sap-wood. 


20  STEM. 

The  inside  of  the  bark  of  such  stems  has 
also  the  technical  name  of  Liher. 

The  Heart-wood  was,  when  young,  Albur- 
num, and  afterwards  changed  its  nature,  by- 
becoming  the  receptacle  of  certain  secretions 
peculiar  to  the  species. 

Hence  the  greater  durability  of  Heart-wood 
than  of  Sap-wood.  While  the  latter  is  newly 
formed  empty  tissue,  almost  as  perishable  as 
bark  itself,  the  former  is  protected  against  de- 
struction by  the  introduction  of  secretions  that 
become  solid  matter,  which  is  often  insoluble 
in  water,  and  never  permeable  to  air.  • 

The  secretions  by  which  Heart-wood  is  soli- 
dified are  prepared  in  the  leaves,  whence  they 
are  sent  downwards  through  the  bark,  and  from 
the  bark  communicated  to  the  central  part  of 
the  stem. 

The  channels  through  which  this  communi- 
cation takes  place  are  called  Medullary  Rays, 
or  Silver  Grain. 

Medullary  rays  are  plates  of  cellular  tissue, 
in  a  very  compressed  state,  passing  from  the 
pith  into  the  bark.  They  are  what  form  the 
cross  grain  of  most  of  our  ornamental  woods. 

The  wood  itself  is  composed  of  tubes  con- 
sisting of  woody  fibre  and  vascular  tissue,  im- 
bedded longitudinally  in  cellular  substance. 


STEM.  21 

This  cellular  substance  only  developes  hori- 
zontally ;  and  it  is  to  it  that  the  peculiar  char- 
acter of  different  kinds  of  wood  is  chiefly  due. 

For  this  reason  the  wood  of  the  stock  of  a 
grafted  plant  will  never  become  like  that  of  its 
scion,  although,  as  will  be  hereafter  seen,  the 
woody  matter  of  the  stock  must  all  originate  in 
the  scion. 

The  stem  of  an  Exogenous  plant  may  there- 
fore be  compared  to  a  piece  of  linen,  of  which 
the  weft  is  composed  of  cellular  tissue,  and  the 
warp  of  fibrous  and  vascular  tissue. 

In  the  spring  and  autumn  a  viscid  juice  is 
secreted  between  the  wood  and  the  liber,  called 
the  Camhium. 

This  Cambium  appears  to  be  the  matter  out 
of  which  the  cellular  horizontal  substance  of 
the  stem  is  organised. 

In  Endogenous  stems,  such  as  the  Palm,  the 
portion  at  the  circumference  is  harder  than  that 
in  the  centre ;  and  there  is  no  separable  bark. 

Their  stems  consist  of  bundles  of  woody 
matter,  imbedded  in  cellular  tissue,  and  com- 
posed of  vascular  tissue  surrounded  by  woody 
fibre. 

The  stem  is  not  only  the  depository  of  tlie 
peculiar  secretions  of  species,  but  is  also  the 


22  LEAF-BUDS. 

medium  through  which  the  sap  flows  in  its  pas- 
sage from  the  roots  into  the  leaves. 

In  Exogenous  stems  it  certainly  rises  through 
tlie  alburnum,  and  descends  through  the  bark. 

In  Endogenous  stems  it  probably  rises 
through  the  bundles  of  wood,  and  descends 
through  the  cellular  substance ;  but  this  is  un- 
certain. 

Stems  have  the  power  of  propagating  an 
individual  only  by  means  of  their  Leaf-buds. 
If  destitute  of  Leaf-buds,  they  have  no  power 
of  multiplication,  except  fortuitously. 


Leaf-buds. 

Leaf-buds  are  rudiments  of  branches,  en- 
closed within  scales,  which  are  imperfectly 
formed  leaves. 

All  the  leaf-buds  upon  the  same  branch  are 
constitutionally  and  anatomically  the  same. 

They  are  of  two  kinds ;  viz.  regular  or  nor- 
mal^ and  adventitious  or  latent. 

Regular  leaf-buds  are  formed  in  the  angle 
of  the  leaf  and  the  stem,  called  the  axil,  at  the 
origin  of  the  leaf —  all  bodies  growing  in  that 
angle,  are  called  axillary. 


LEAF-BUDS.  23 

They  arc  capable  of  propagating  the  indi- 
vidual from  which  they  originate. 

They  are  at  first  nourished  by  the  fluid  lying 
in  the  pith,  from  which  it  is  probable  they  take 
their  rise,  as  may  be  seen  in  a  cross  slice  of 
the  pine  made  at  a  knot,  or  just  at  the  axil,  but 
they  finally  establish  for  themselves  a  commu- 
nication with  the  soil  by  the  woody  matter 
which  they  send  downwards. 

Their  force  of  development  will  be  in  pro- 
portion to  their  nourishment ;  and,  consequently, 
when  it  is  wished  to  procure  a  young  shoot  of 
unusual  vigor,  all  other  shoots  in  the  vicinity 
are  prevented  growing,  so  as  to  accumulate  for 
one  shoot  only  all  the  food  that  would  other- 
wise have  been  consumed  by  several. 

Cutting  back  to  a  few  eyes  is  an  operation 
in  pruning  to  produce  the  same  effect,  by 
directing  the  sap,  as  it  ascends,  into  tv/o  or 
three  buds  only,  instead  of  allowing  it  to  ex- 
pend itself  upon  all  the  others  which  are  cut 
away. 

It  is  better  in  many  cases  of  flowering  plants 
and  fruits  to  rub  off  all  buds  but  those  wished 
to  be  left,  before  they  become  branches. 

When  leaf-buds  grow,  they  develope  in  three 
directions;  the  one  horizontal,  the  other  up- 
ward, and  the  third  downward. 


24  LEAF-BUDS. 

The  horizontal  development  is  confined  to 
the  cellular  system  of  the  bark,  pith,  and  me- 
dullary rays. 

The  upwaj.'d  and  downward  developments 
are  confined  to  the  woody  fibre  and  vascular 
tissue. 

In  this  respect  they  resemble  seeds;  from 
which,  they  differ  physiologically  in  propagating 
the  individual,  while  seeds  can  only  propagate 
the  species. 

When  they  disjoin  from  the  stem  that  bears 
them,  they  are  called  hdhs. 

In  some  plants,  a  bud,  when  separated  from 
its  stem,  will  grow  and  form  a  new  plant,  if 
placed  in  circumstances  favorable  to  the  pre- 
servation of  its  vital  powers. 

But  this  property  seems  confined  to  plants 
having  a  firm,  woody,  perennial  stem. 

Such  buds,  when  detached  from  their  parent 
stem,  send  roots  downwards  and  a  stem  up- 
wards. 

But  if  the  buds  are  not  separated  from  the 
plant  to  which  they  belong,  the  matter  they 
send  downwards  becomes  wood  and  liber,  and 
the  stems  they  send  upwards  become  branches. 
Hence  it  is  said  that  wood  and  liber  are  formed 
by  the  roots  of  leaf-buds. 


LEAF-BUDS.  25 

If  no  leaf-buds  arc  called  into  action,  there 
will  be  no  addition  of  wood :  and,  consequently, 
the  destruction  or  absence  of  leaf-buds  is  ac- 
companied by  the  absence  of  wood;  as  is 
proved  by  a  shoot,  the  upper  buds  of  which 
are  destroyed  and  the  lower  allowed  to  devel- 
ope.  The  lower  part  of  the  shoot  will  increase 
in  diameter ;  the  upper  will  remain  of  its  origi- 
nal dimensions. 

The  quantity  of  wood,  therefore,  depends 
upon  the  quantity  of  leaf-buds  that  develope. 

It  is  of  the  greatest  importance  to  bear  this 
in  mind  in  pruning  timber  trees  ;  for  excessive 
pruning  must  necessarily  be  injurious  to  the 
quantity  of  produce. 

If  a  cutting  with  a  leaf-bud  on  it  be  placed 
in  circumstances  fitted  to  the  development  of 
the  latter,  it  will  grow  and  become  a  new 
plant. 

If  this  happens  when  the  cutting  is  inserted 
in  the  earth,  the  new  plant  is  said  by  gardeners 
to  he  upon  its  own  hottom. 

But  if  it  happens  when  the  cutting  is  applied 
to  the  dissevered  end  of  another  individual, 
called  a  stock,  the  roots  are  insinuated  into  the 
tissue  of  the  stock,  and  a  plant  is  said  to  he 
grafted ;  the  cutting  being  called  a  scion. 
3 


26  LEAF-BUDS. 

There  is,  therefore,  little  difference  between 
cuttings  and  scions,  except  that  the  former  root 
into  the  earth,  the  latter  into  another  plant. 

But  if  a  cutting  of  the  same  plant  without  a 
leaf-bud  upon  it  be  placed  in  the  same  circum- 
stances, it  will  not  grow,  but  will  die. 

Unless  its  vital  powers  are  sufficient  to  enable 
it  to  develope  an  adventitious  leaf-bud. 

A  leaf-bud  separated  from  the  stem  will  also 
become  a  new  individual,  if  its  vital  energy  is 
sufficiently  powerful. 

And  this,  whether  it  is  planted  in  earth,  into 
which  it  roots,  like  a  cutting,  or  in  a  new  in- 
dividual to  which  it  adheres  and  grows  like  a 
scion.  In  the  former  case  it  is  called  an  eye^ 
in  the  latter  a  hud. 

Every  leaf-bud  has,  therefore,  its  own  dis- 
tinct system  of  life,  and  of  growth. 

And  as  all  the  leaf-buds  of  an  individual  are 
exactly  alike,  it  follows  that  a  plant  is  a  collec- 
tion of  a  great  number  of  distinct  identical 
systems  of  life,  and  consequently  a  compound 
individual. 

Regular  leaf-buds  being  generated  in  the 
axils  of  the  leaves,  it  is  there  that  they  are 
always  to  be  sought. 

And  if  they  cannot  be  discovered  by  ocular 


LEAF-BUDS.  27 

inspection,  it  may  nevertheless  be  always  in- 
ferred with  confidence  that  they  exist  in  such 
situations,  and  may  possibly  be  called  from 
their  dormant  state  into  life. 

Hence,  wherever  the  scar  of  a  leaf,  or  the 
remains  of  a  leaf,  can  be  discovered,  there  it  is 
to  be  understood  that  the  rudiments  exist  of  a 
system  of  life  which  may  be,  by  favorable  cir- 
cumstances, called  into  action. 

Hence,  all  parts  upon  which  leaves  have  ever 
grown  may  be  made  use  of  for  purposes  of  pro- 
pagation. 

From  these  considerations  it  appears  that 
the  most  direct  analogy  between  the  Animal 
and  Vegetable  Kingdoms  is  with  the  Polypes 
of  the  former. 

Adventitious  leaf-buds  are  in  all  respects  like 
regular  leaf-buds,  except  that  they  are  not 
formed  at  the  axils  of  leaves,  but  develope 
occasionally  from  all  and  any  parts  of  a  plant. 

They  are  occasionally  produced  by  roots,  by 
solid  wood,  or  even  by  leaves  and  flowers. 

Hence,  roots  solid  wood,  or  even  leaves  and 
flowers  may  in  particular  cases  be  used  as 
means  of  propagation. 

But  as  the  development  of  adventitious  buds 
is  extremely  uncertain,  such  means  of  propaga- 


28  LEAF-BUDS. 

tion  can  never  be  calculated  on ;  and  form  no 
part  of  the  science  of  cultivation. 

The  cause  of  the  formation  of  adventitious 
leaf-buds  is  unknown. 

From  certain  experiments  it  appears  that 
they  may  be  generated  by  sap  in  a  state  of 
great  accumulation  and  activity. 

Consequently,  whatever  tends  to  the  accu- 
mulation of  sap  in  an  active  state  may  be 
expected  to  be  conducive  to  the  formation  of 
adventitious  leaf-buds. 

When  a  hard  woody  plant  is  cut  down  after 
transplantation,  adventitious  leaf-buds  will  start 
from  all  parts  of  the  stem.  They  originate  and 
are  pushed  out  from  the  centre,  and  are  caused 
by  the  accumulated  sap. 

The  leaf-bud  and  the  flower-bud  are  the 
same  in  the  earliest  stage  of  their  organization, 
but  soon  after,  the  change  takes  place  which  is 
visible  in  most  fruit  trees  as  soon  as  the  sap 
begins  to  flow. 

The  determination  of  these  buds  to  leaf  or 
blossom-buds,  no  doubt  depends  on  the  quantity 
and  quality  of  the  sap  stored  up  during  the 
winter.  When  excessive  vigor  is  produced  in 
trees,  it  is  favorable  to  the  production  of  leaf- 
buds,  and  consequently  of  wood.     On  the  con- 


LEAVES,  29 

trary,  wlien  rapid  and  vigorous  vegetation  is 
checked,  blossom-buds,  and  consequently,  fruit 
will  be  in  abundance  —  thus,  fruit  is  seldom 
borne  on  the  thick  vigorous  shoots  of  the 
peacli,  &c.,  but  generally  on  the  slender  ones. 

If  an  unproductive  tree  is  transplanted,  it  often 
becomes  productive  from  the  check  given. 

In  India  and  China,  trees  are  brought  to  bear 
fruit  by  cutting  the  roots  or  exposing  them  to 
dryness. 

Leaves. 

Leaves  are  expansions  of  bark,  traversed  by 
veins. 

The  veins  consist  of  spiral  vessels  enclosed 
in  woody  fibre ;  they  originate  in  the  medullary 
sheath  and  liber;  and  they  are  connected  by 
loose  cellular  tissue  which  is  full  of  cavities 
containing  air. 

This  cellular  tissue  consists  of  two  layers,  of 
which  the  upper  is  composed  of  small  cells 
perpendicular  to  the  outer  skin,  and  the  lower 
of  small  cells  parallel  with  the  outer  skin. 

These  small  cells  are  arranged  so  as  to 
leave  numerous  open  passages  among  them 
for  the  circulation  of  air  in  the  inside  of  a 
3* 


30  LEAVES. 

leaf.     Cellular  tissue  of  this  nature  is  called 
cavernous. 

The  skin  covering  the  leaf  called  cuticle,  is 
formed  of  one  or  more  layers  of  depressed 
cellular  tissue,  which  is  generally  hardened, 
and  always  dry  and  filled  with  air. 

Between  many  of  the  cells  of  the  cuticle  are 
placed  apertures  or  pores  called  stomata,  which 
have  the  power  of  opening  and  closing  as  cir- 
cumstances may  require. 

It  is  by  means  of  this  apparatus  that  leaves 
prepare  the  sap  which  they  absorb  from  the 
alburnum,  or  new  wood,  converting  it  into  the 
secretions  peculiar  to  the  species. 

Their  cavernous  structure  enables  them  to 
expose  the  greatest  possible  surface  of  their 
cellular  tissue  to  the  action  of  the  atmosphere. 

Their  cuticle  is  a  non-conducting  skin,  which 
protects  them  from  great  variations  in  tempera- 
ture, and  through  which  gaseous  matter  will  pass 
readily. 

Their  stomata  are  pores  that  are  chiefly  in- 
tended to  facilitate  evaporation ;  for  which  they 
are  well  adapted  by  the  power  they  possess  of 
opening  or  closing  as  circumstances  may  re- 
quire. 

They  arc  also  intended  for  facilitatmg  the 


LEAVES.  31 

rapid  emission  of  air,  when  it  is  necessary  that 
sucli  a  function  should  be  performed. 

The  action  and  functions  of  stomata  being 
of  such  vital  importance,  it  is  absolutely  neces- 
sary to  the  health  of  a  plant  that  they  be  not 
choked  up  with  dust  or  dirt  or  injured  by  in- 
sects, the  cleaner  therefore  the  leaves  of  a  plant 
are  kept  the  more  it  will  flourish. 

Leaves  growing  in  air  are  covered  with  a 
cuticle. 

Leaves  growing  under  water  have  no  cuticle. 

All  the  secretions  of  plants  being  formed  in 
the  leaves,  or  at  least  the  greater  part,  it  fol- 
lows that  secretions  cannot  take  place  if  leaves 
are  destroyed. 

And  as  this  secreting  property  depends  upon 
specific  vital  powers  connected  with  the  decom- 
position of  carbonic  acid,  and  called  into  action 
only  when  the  leaves  are  freely  exposed  to 
light  and  air,  it  also  follows  that  the  quantity 
of  secretion  will  be  in  direct  proportion  to  the 
quantity  of  leaves,  and  to  their  free  exposure 
to  light  and  air. 

The  leaf  therefore  is  a  beautiful  contrivance 
for  exposing  a  large  surface  of  crude  sap  to  the 
influence  of  the  external  air  and  solar  light,  by 
the  operation  of  which  it  is  rendered  capable 


32  LEAVES. 

of  being  converted  into  the  different  substances 
required  for  the  growth  of  the  plant  and  the 
production  of  its  fruit  and  seed. 

The  Hght  of  the  sun  striking  on  a  leaf  causes 

1.  Decomposition  of  carbonic  acid,  by  which 
carbon  in  different  vegetable  forms  enters  into 
the  composition  chiefly  of  the  solid  parts  of  the 
plant  —  this  is  in  proportion  to  the  intensity  of 
the  light  to  which  it  is  exposed  ;  hence,  plants 
grown  in  the  shade  are  weak,  and  vice  versa. 

2.  Extrication  of  nitrogen. 

3.  Insensible  perspiration  or  evaporation; 
hence  this  does  not  take  place  during  the 
night. 

The  health  of  plants  depends  much  on  the 
proper  adjustment  between  the  quantity  of 
juices  taken  up  by  the  roots,  and  the  perspira- 
tion of  the  leaves.  If  they  are  exposed  to  too 
much  solar  light,  the  perspiration  is  greater 
than  the  roots  can  supply,  and  the  leaves  flag : 
when  transplanted,  if  watered  in  the  evening, 
the  roots  become  supplied  with  moisture  and 
juices,  the  perspiration  ceasing  during  the  night, 
this  action  recovers  its  equiUbrium,  and  the 
leaves  are  seen  erect  in  the  morning. 

The  quantity  of  light  or  shade  which  can  be 
borne  by  a  plant,  depends  on  the  number,  form 


LEAVES.  33 

and  fiction  of  the  stomata,  and  as  these  vary 
considerably  in  different  plants,  it  is  evident 
that  some  are  created  to  prefer  shade,  others  to 
prefer  light. 

In  this  climate  where  the  atmosphere  is  so 
pure  and  free  from  mist  and  vapor,  where  solar 
light  is  so  intense  during  the  summer,  attention 
to  these  principles  is  peculiarly  requisite.  On 
this  subject,  more  will  be  found  under  the  con- 
siderations of  light,  air,  perspiration,  and  trans- 
plantation. 

The  usual  position  of  leaves  is  spiral,  at 
regularly  increasing  or  diminishing  distances ; 
they  are  then  said  to  be  alternate. 

But  if  the  space  of  the  stem  called  the  axis, 
that  separates  two  leaves,  is  reduced  to  nothing 
at  alternate  intervals,  they  become  opposite. 

And  if  the  spaces  that  separate  several  leaves 
be  reduced  to  nothing,  they  become  verticillate 
or  whorled. 

Opposite  and  verticillate  leaves,  therefore, 
differ  from  alternate  leaves  only  in  the  spaces 
that  separate  them  being  reduced  to  nothing. 


34  FLOWERS. 


Flowers. 


Flowers  consist  of  two  principal  parts,  the 
interior  or  those  destined  to  form  and  perfect 
the  seed,  called  Stamens  and  Pistils,  and  the 
exterior  or  those  destined  to  envelope,  protect 
and  ornament  the  former,  called  Floral  En- 
velopes. 

Of  these,  the  latter  constitute  what  is  popular- 
ly considered  the  flower ;  although  the  former 
are  the  only  parts  that  are  absolutely  essential 
to  it. 

Some  flowers  have  only  one  envelope,  some 
none,  as  the  willow. 

However  diflerent  they  may  be  in  appear- 
ance from  leaves,  they  are  all  formed  of  those 
organs  in  a  more  or  less  modified  state,  and 
altered  in  a  greater  or  less  degree  by  mutual 
adhesion. 

The  Floral  Envelopes  consist  of  two  or  more 
series  called  whorls  of  transformed  leaves ;  of 
which  part  is  calyx,  its  leaves  being  called 
sepals,  and  part  corolla,  its  leaves  being  called 
petals. 

The  stamens  and  pistils  arc  also  transformed 
leaves. 


FLOWERS.  35 

The  calyx  is  always  the  outermost,  the 
corolla  is  always  the  innermost  whorl ;  and  if 
there  is  but  one  floral  envelope,  that  one  is 
called  calyx. 

Usually  the  calyx  is  green,  and  the  corolla 
colored  and  more  highly  developed  ;  but  the 
reverse  is  frequently  the  case,  as  in  Fuchsia, 
llibes  sanguineum,  &c. 

A  Flower  being,  then,  an  axis,  or  stem  sur- 
rounded by  leaves,  it  is  in  reality  a  stunted 
branch ;  that  is,  one  the  growth  of  which  is 
checked,  and  its  power  of  elongation  destroyed. 

That  flowers  are  stunted  branches  is  proved, 
firstly^  by  all  their  parts,  especially  the  most 
external,  occasionally  reverting  to  the  state  of 
ordinary  leaves ;  secondly^  by  their  parts  being 
often  transformed  into  each  other ;  and,  thirdly, 
by  the  whorls  of  flower-buds  being  dislocated 
and  actually  converted  into  branches  when- 
ever any  thing  occurs  to  stimulate  them  exces- 
sively. 

Their  most  essential  distinctive  character 
consists  in  the  buds  at  the  axils  of  their  leaves 
being  usually  dormant,  while  those  in  the  axils 
of  ordinary  leaves  are  usually  active. 

But  an  extraordinary  case  is  recorded  by  Mr. 
Knight  of  potatoes  growing  in  the  angles  (axils) 
of  the  sepals  and  of  the  petals  of  the  flower. 


36  FLOWEKS. 

For  this  reason  while  leaf-buds  can  be  used 
for  the  purpose  of  propagation,  flower-buds 
cannot  usually  be  so  employed. 

Being  stunted  branches,  their  position  on  the 
stem  is  the  same  as  that  of  developed  branches. 
And  as  there  is  in  all  plants  a  veiy  great 
difference  in  the  development  of  leaf-buds, 
some  growing  readily  into  branches,  others 
only  unfolding  their  leaves  without  elongating, 
and  many  remaining  altogether  dormant,  it 
follows  that  flower-buds  may  form  upon  plants 
of  whatever  age  and  in  whatever  state. 

But  to  produce  a  general  formation  of  flow- 
er-buds it  is  necessary  that  there  should  be 
some  general  predisposing  constitutional  cause 
independent  of  accidental  circumstances. 

This  predisposing  cause  is  the  accumulation 
of  sap  and  of  secreted  matter,  as  has  been  be- 
fore explained. 

Therefore  whatever  tends  to  retard  the  free 
flow  of  sap,  and  causes  it  to  accumulate,  will 
cause  the  production  of  flower-buds,  or  fertility. 
And  on  the  other  hand,  whatever  tends  to 
produce  excessive  vigor  causes  the  rapid  mo- 
tion and  dispersion  of  sap,  or  prevents  its  elab- 
oration and  causes  sterility  or  want  of  flower- 
buds. 


FLOWERS.  37 

Transplantation  with  a  partial  destruction  of 
roots,  age,  or  high  temperature  accompanied 
by  a  dry  atmosphere,  training  obliquely  or  in 
an  inverted  direction,  a  constant  destruction  of 
the  extremities  of  young  growing  branches,  will 
all  cause  an  accumulation  of  sap,  and  secre- 
tions ;  and  consequently  all  such  circumstances 
are  favorable  to  the  production  of  flower-buds. 

But  a  richly  manured  soil,  high  temperature, 
with  great  atmospheric  humidity,  or  an  uninter- 
rupted flow  of  sap,  are  all  causes  of  excessive 
vigor,  and  are  consequenfly  unfavorable  to  the 
production  of  flower-buds. 

There  is  a  tendency  in  many  flowers  to  en- 
large, to  alter  their  colors,  or  to  change  their 
appearance  by  a  transformation  and  multiplica- 
tion of  their  parts,  whenever  they  have  been 
raised  from  seeds  for  several  generations,  or 
domesticated. 

The  causes  of  this  tendency  are  probably 
various,  but  being  entirely  unknown,  no  cer- 
tain rules  for  the  production  of  varieties  in 
flowers  can  be  laid  down,  except  by  the  aid  of 
hybridising. 

Tt  often  happens  that  a  single  branch  pro- 
duces flowers  different  from  those  produced  on 
4 


38  FLOWERS. 

Other  brandies.  This  is  technically  called  a 
sport. 

As  every  bud  on  that  branch  has  the  same 
specific  vital  principle,  a  bud  taken  from  such  a 
branch  will  produce  an  individual,  the  whole  of 
whose  branches  will  retain  the  character  of  the 
sport. 

Consequently,  buds  by  accidental  variety 
may  be  made  permanent,  if  the  plant  that 
sports  be  of  a  firm  woody  nature. 

As  flowers  feed  upon  the  prepared  sap  in 
their  vicinity,  the  greater  the  abundance  of  this 
prepared  food,  the  more  perfect  will  be  their 
development. 

Or  the  fewer  the  flowers  on  a  given  branch 
the  more  food  they  will  severally  have  to 
nourish  them,  and  the  more  perfect  will  they 
be. 

The  beauty  of  flowers  will  therefore  be  in- 
creased either  by  an  abundant  supply  of  food, 
or  by  a  diminution  of  their  numbers  (thinning), 
or  by  both.  The  business  of  the  pruner  is  to 
cause  these  by  his  operations. 

The  beauty  of  Flowers  depends  upon  their 
free  exposure  to  light  and  air,  because  it  con- 
sists in  the  richness  of  their  colors,  and  their 
colors  are  only  formed  by  the  action  of  those 
two  agents. 


FLOWERS.  39 

Hence,  Flowers  produced  in  dark  or  shady 
confined  situations  are  either  imperfect,  or  des- 
titute of  their  habitual  size  and  beauty. 

Double  Flowers  are  those  in  which  the  sta- 
mens are  transformed  into  petals ;  or  in  which 
the  latter,  or  the  sepals,  are  multiplied.  They 
should  not  be  confounded  with  Proliferous  and 
Discoid  Compound  Floicers.  This  difference 
will  be  explained  immediately. 

Although  no  certain  rules  for  the  production 
of  double  flowers  can  be  laid  down,  yet  it  is 
probable  that  those  flowers  have  the  greatest 
tendency  to  become  double,  in  which  the  parts 
are  habitually  multiplied. 

Plants  whose  flowers  have  naturally  nume- 
rous stamens  and  pistils,  are  those  which 
usually  become  double,  these  being  the  parts 
generally  transformed  into  petals. 

Double  Flowers  are  therefore  least  to  be  ex- 
pected in  plants  with  fewest  stamens. 

Whenever  the  parts  of  a  Flower  adhere  by 
their  edges,  forming  what  are  called  one  sepal- 
led  {gamosepaloiis)  calyxes  or  one  petaled 
(gamopetalous)  corollas,  or  where  the  stamens 
are  combined  either  into  one  or  few  parcels,  the 
tendency  to  multiplication  seems  checked,  but 
this  is  by  no  means  general,  as  we  have  double 


40  FLOWERS. 

Campanula  which  is  one  petaled  and  double 
Hibiscus  and  CamelUa  where  the  stamens  are 
combined. 

ProUferous  Flowers  are  those  in  which  parts 
that  usually  have  all  their  axillaiy  buds  dor- 
mant, accidently  develope  such  buds ;  as  in 
certain  Roses,  in  which  a  branch  grows  up 
from  the  centre  of  a  rose,  or  as  it  is  technically 
said  the  carpellary  leaves  develope  leaf-buds 
in  their  axils,  so  that  the  flower  becomes  a 
branch,  the  lower  leaves  of  which  are  colored 
and  transformed,  and  the  upper  green,  and  in 
their  ordinary  state. 

Discoid  compound  Flowers  are  those  in  which 
the  central  florets  of  a  flower-head  acquire 
corollas,  like  those  of  the  circumference,  one 
side  strap  shaped,  as  in  the  Dahlia ;  the  culti- 
vated varieties  of  which  should  be  called  discoid, 
and  not  double. 

These  two  last  are  so  essentially  different 
from  double  flowers,  that  whatever  laws  may 
be  supposed  to  govern  the  production  or  ameli- 
oration of  double  Flowers,  can  have  no  relation 
to  proliferous  or  discoid  compound  Flowers. 


STAMENS    AND    PISTILS.  41 


Stamens  and  Pistils. 

The  Stamens  and  Pistils  are  known  to  be 
modifications  of  leaves,  because  they  very  fre- 
quently are  transformed  into  petals  which  are 
demonstrably  such ;  aiKl  because  they  occa- 
sionally revert  to  the  state  of  leaves.  In  the 
double  poppy  the  stamens  change  into  petals, 
in  the  double  anemone  and  ranunculus  the 
pistils  undei'go  the  same  transformation. 

The  stamens  bear  at  their  summits  an  organ, 
called  the  anther,  which  contains  a  powder 
called  poUen. 

When  the  anther  is  full  grown  it  opens  and 
ejects  the  pollen,  either  dispersing  it  in  the 
air  in  consequence  of  the  elasticity  with  which 
it  opens  ;  or  depositing  it  upon  the  summit  of 
the  pistil  called  stigma  ;  or  exposing  it  to  the 
action  of  wind,  or  such  other  disturbing  causes 
as  may  liberate  it  from  its  case. 

The  pollen  consists  of  exceedingly  minute 
hollow  balls,  or  cases,  containing  myriads  of 
particles  called  granules,  which  are  the  fer- 
tilising principle  of  the  stamens. 

The  pistil  has  at  its  base  one  or  more 
cavities  or  cells  called  in  a  ripe  state  seed  ves- 
4* 


42  STAMENS    AWD    PISTILS. 

sels,  in  which  bodies  called  ovula  are  placed  ; 
and  at  its  summit  one  or  more  secreting  sur- 
faces called  stigmata. 

The  ovula  are  the  rudiments  of  seeds. 

If  the  fertilising  powder  of  the  pollen  come 
in  contact  with  the  stigma,  the  ovula  in  the 
cells  of  the  pistil  are  vivified,  and  become 
seeds. 

Late  microscopic  discoveries  render  it  al- 
most certain  that  the  granules  of  pollen  are  the 
true  seeds  deposited  in  the  ovula  by  means  of 
tubes  or  elongations  of  the  skin  of  the  hollow 
balls  of  pollen  —  there  partly  developed  and  se- 
cured by  various  coverings  called  integuments, 
until  the  proper  period  and  circumstances  arise 
for  their  farther  growth  in  the  earth  —  and  that 
the  present  idea  of  vivification  by  pollen  and  the 
sexes  of  plants  is  either  not  correct  or  not  pro- 
perly understood. 

In  wild  plants  a  stigma  is  usually  acted  upon 
only  by  the  pollen  of  the  stamens  which  belong 
to  it. 

In  this  case  the  seeds  thus  vivified  will,  when 
sown,  produce  new  individuals,  differing  very 
little  from  that  by  which  they  were  themselves 
produced. 

And,  therefore,  wild  plants  are  for  the  most 


STAMENS    AND    PISTILS.  43 

part  multiplied  from  generation  to  generation 
without  change. 

But  it  is  possible  to  cause  deviations  from 
this  law,  by  artificial  means. 

If  the  pollen  of  one  species  is  placed  upon 
the  stigma  of  another  species,  the  ovula  will  be 
vivified  ;  and  what  is  called  a  hylrid  plant  will 
be  produced  by  those  ovula  when  they  shall 
have  grown  to  be  seeds. 

Hybrid  plants  are  different  from  both  their 
parents,  and  are  generally  intermediate  in  cha- 
racter between  them. 

Reasoning  from  analogy  it  was  formerly 
thought  that  hybrids  were  sterile  and  could  not 
perfect  seeds,  experience  however  teaches  that 
this  is  not  the  case  ;  but  in  woody  and  other 
plants  where  hybridisation  has  produced  fine 
varieties  either  of  fruit  or  flowers,  these  varieties 
are  usually  propagated  by  buds,  cuttings,  and 
scions. 

The  power  of  hybridisation  will  probably 
when  experience  shall  have  matured  and 
science  arranged  more  numerous  results,  be- 
come the  most  correct  test  of  botanical  divi- 
sions into  genera.  Great  care  is  requisite  in 
making  experiments  on  hybridisation  to  cut  out 
the  anthers  of  one  of  the  plants  experimented 


44  STAMENS    AND    PISTILS. 

on  previous  to  their  bursting,  to  apply  the 
pollen  of  the  other  when  in  perfection,  and 
to  place  the  plant  where  none  others  of  the 
genus  are  in  the  vicinity. 

The  tropical  warmth  of  the  sun  in  this  coun- 
try, is  very  favorable  for  maturing  the  pollen 
of  all  plants,  particularly  those  from  tropical 
regions,  thus  facilitating  such  experiments. 

It  usually  happens  that  the  hybrid  has  the 
constitution  and  general  aspect  of  the  pollinife- 
rous  parent ;  but  is  influenced  in  secondary 
characters  by  the  peculiarity  of  the  female 
parent.  See  more  on  thissubject under  article 
Fruit. 

This  should  always  be  borne  in  mind  in  pro- 
curing new  hybrid  plants. 

Really  hybrid  plants  must  not  be  confounded 
with  such  as  are  spurious,  in  consequence  of 
their  origin  being  between  two  varieties  of  the 
same  species,  and  not  two  species  of  the  same 
genus. 

Hybrid  plants,  are  often  more  abundant  flow- 
erers  than  either  parent. 

This  is,  probably,  connected  with  constitu- 
tional debility. 


FRUIT.  45 


Fruit. 


Fruit,  strictly  speaking,  is  the  pistil  arrived  at 
maturity. 

When  the  calyx  adheres  to  the  pistil  and 
grows  with  it  to  maturity,  the  fruit  is  called 
inferior ;  as  the  Apple. 

But  when  the  pistil  alone  ripens,  there 
being  no  adhesion  to  it  on  the  part  of  the 
calyx,  the  fruit  is  called  superior;  as  the 
Peach. 

The  fruit  is,  therefore,  in  common  language, 
the  flower,  or  some  part  of  it,  arrived  at  its 
most  complete  state  of  existence  ;  and,  con- 
sequently, is  itself  a  portion  of  a  stunted 
branch. 

The  nature  of  its  connection  with  the  stem 
is  therefore  the  same  as  that  of  the  branches 
with  each  other,  or  of  leaves  with  their  stem. 

A  superior  Fruit  consisting  only  of  one,  or 
of  a  small  number  of  transformed  leaves,  it 
has  little  or  no  power  of  forming  a  communi- 
cation with  the  earth  and  of  feeding  itself,  as 
real  branches  have. 

It  has  also  very  little  adhesion  to  its  branch  ; 
so  that  but  slight  causes  are  sufficient  to  detach 


46  FRUIT. 

it  from  the  plant,  especially  at  an  early  age, 
when  all  its  parts  are  tender. 

Hence  the  difficulty  of  causing  Peaches  and 
the  like  to  stone^  or  to  pass  over  that  age,  in 
which  the  vascular  bundles  that  join  them  to 
the  branch  become  woody,  and  secure  them  to 
their  place. 

For  the  same  reason  they  are  fed  almost 
entirely  by  other  parts,  upon  secreted  matter 
which  they  attract  to  themselves,  elaborate, 
and  store  up  in  the  cavities  of  their  tissue. 

The  office  of  feeding  such  fruit  is  performed 
by  young  branches,  which  transmit  nutriment 
to  it  through  the  bark. 

But  as  young  branches  can  only  transmit 
nutriment  downwards,  it  follows  that  unless  a 
fruit  is  formed  on  a  part  of  a  branch  below  a 
leaf-bud,  it  must  perish. 

Unless  there  is  some  active  vegetation  in  the 
stem  above  the  branch  on  which  it  grows ; 
when  it  may  possibly  live  and  feed  upon  secre- 
tions attracted  by  it  from  the  main  stem ;  thus 
in  pruning  the  peach  and  other  trees  with  siqje- 
rior  fruit  in  the  spring  it  is  always  necessary  to 
leave  one  or  two  leaf-buds  above  the  flower-bud. 

But  inferior  fruit,  consisting  always  of  the 
calyx  in   addition  to  the   pistil,   has   a   much 


FRUIT.  47 

more  powerful  communication  with  the  branch ; 
each  division  of  its  calyx  having  at  least  one 
bundle  of  vascular  and  fibrous  tissue,  passing 
from  it  into  the  branch,  and  acting  as  a  stay 
upon  the  centre  to  prevent  its  breaking  off. 

Such  fruit  may  be  supposed  much  more 
capable  of  establishing  a  means  of  attracting 
secretions  from  a  distance  ;  and,  consequently, 
is  less  liable  to  perish  from  want  of  a  supply  of 
food. 

It  is  therefore  not  so  important  that  an  infe- 
rior fruit  should  be  furnished  with  growing 
branches  above  it,  instance,  Apple,  Pear. 

Fruit  is  exclusively  fed  by  the  secretions 
prepared  for  it  by  other  parts ;  it  is  therefore 
affected  by  nearly  the  same  circumstances  as 
flowers. 

It  will  be  large  in  proportion  to  the  quantity 
of  food  the  stem  can  supply  to  it :  and  small 
in  proportion  to  the  inability  of  the  stem  to 
nourish  it. 

For  this  reason,  when  trees  are  weak  they 
should  be  allowed  to  bear  very  little,  if  any 
fruit ;  because  a  crop  of  fruit  can  only  tend  to 
increase  their  debility. 

And  in  all  cases  each  fruit  should  be  so  far 
separated  from  all  others  as  not  to  be  robbed  of 
its  food  by  those  in  its  vicinity. 


48 


FRUIT. 


We  find  that  nature  has  herself  in  some 
measure  provided  agahist  injury  to  plants  by 
excessive  fecundity,  in  giving  them  a  power  of 
tlirowing  off  flowers,  the  fruit  of  which  cannot 
be  supported. 

The  flavor  of  fruit  depends  upon  the  exist- 
ence of  certain  secretions,  especially  of  acid 
and  sugar ;  flavor  will,  consequently,  be  regu- 
lated by  the  circumstances  under  which  fruit  is 
ripened. 

The  ripening  of  fruit  is  the  conversion  of 
acid  and  other  substances  into  sugar. 

As  the  latter  substance  cannot  be  obtained  at 
all  in  the  dark,  is  less  abundant  in  fruit  ripened 
in  diffused  light,  and  most  abundant  in  fruit  ex- 
posed to  the  direct  rays  of  the  sun,  the  conver- 
sion of  matter  into  sugar  occurs  under  the  same 
circumstances  as  the  decomposition  of  carbonic 
acid. 

Therefore,  if  fruit  be  produced  in  situations 
much  exposed  to  the  sun,  its  sweetness  will  be 
augmented. 

And  in  proportion  as  it  is  deprived  of  the 
sun's  direct  rays  that  quality  will  diminish. 

Fruit  produced  under  circumstances  of  great 
moisture  and  diminution  of  solar  light,  as  in 
seasons   of  continued   rain  where    the  sky  is 


FRUIT. 


49 


mucli  clouded,  will  be  larger,  but  the  flavor 
will  be  less  sweet  and  agreeable  —  this  is  often 
the  case  with  the  large  strawberries. 

So  that  a  fruit  which  when  exposed  to  the 
sun  is  sweet,  when  grown  where  no  direct 
light  will  reach  it  will  be  acid ;  as  Pears, 
Cherries,  &c. 

Hence  acidity  may  be  corrected  by  exposure 
to  light ;  and  excessive  sweetness,  or  insipidity, 
by  removal  from  light. 

Judicious  pruning,  therefore,  so  as  to  admit 
all  the  possible  light  and  air  to  the  fruit,  is  ad- 
vantageous, but  care  must  be  taken  that  it  be 
not  pursued  to  the  injury  of  the  plant. 

It  is  the  property  of  succulent  fruits  which 
are  acid  when  wild  to  acquire  sweetness  when 
cultivated,  losing  a  part  of  their  acid. 

This  probably  arises  from  the  augmentation 
of  the  cellular  tissue,  which  possibly  has  a 
greater  power  than  woody  or  vascular  tissue 
of  assisting  in  the  formation  of  sugar. 

As  a  certain  quantity  of  acid  is  essential  to 
render  fruit  agreeable  to  the  palate,  and  as  it  is 
the  property  of  cultivated  fruits  to  add  to  their 
saccharine  matter,  but  not  to  form  more  acid 
than  when  wild,  it  follows  that,  in  selecting  wild 
fruits  for  domestication,  those  which  are  acid 
5 


50  FRUIT. 

should  be  preferred,  and  those  which  are  sweet 
or  insipid  rejected. 

Unless  recourse  is  had  to  hybridism ;  when 
a  wild  insipid  fruit  may  be  possibly  improved, 
or  may  be  the  means  of  improving  something 
else. 

It  is  very  much  upon  such  considerations  as 
the  foregoing  that  the  rules  of  training  must  de- 
pend. 

The  effect  of  removing  a  ring  of  bark  from 
the  fruit-bearing  branch,  is  to  increase  con- 
siderably the  size  of  the  fruit  above  the  ring, 
by  retaining  the  juices  of  the  wood  which  are 
prevented  from  returning,  the  communication 
being  cut  off.  But  if  the  ring  is  too  wide  or 
the  branch  on  which  it  is  practised  too  small,  a 
morbid  state  of  early  maturity  is  produced,  and 
the  fruit  is  worthless.  The  breadth  of  the  ring 
should  be  in  proportion  to  the  thickness  of  the 
branch,  and  in  fruit-bearing  trees  should  be 
performed  as  soon  as  the  flowers  are  apparent 
ui  the  spring. 

Hybridisation  has  been  had  recourse  to  with 
much  success  to  improve  fruits,  but  although 
the  results  have  been  thus  good,  sufficient  care 
has  not  been  taken  to  note  down  the  detail  of 
the   experiments  so  as  to  arrive  at  any  fixed 


SEED.  51 

laws  capable  of  affording  unerring  rules  of 
action. 

My.  Knight  says  he  liad  observed  gene- 
rally a  strong  prevalence  of  the  constitution  and 
habits  of  the  plant  whose  pistil  was  fertilized  by 
the  pollen  of  another.  Mr.  Herbert,  in  discuss- 
ing a  hybrid  Cytisus,  thinks  that  the  plant  with 
the  pistil  influences  the  leaf,  and  that  with  the 
pollen  the  flower  and  fruit.  This  gentleman  in 
his  work  on  AmaryllidaceeE,  has  given  a  most 
interesting  and  detailed  account  of  many  years 
experience  on  Hybridisation. 

The  experience  of  Van  Mons  in  raising  new 
varieties  of  fruit  trees  from  seed,  has  been  emi- 
nently valuable  and  successful,  and  no  doubt 
would  throw  light  on  this  subject. 

Seed. 

The  seed  is  the  ovulum  arrived  at  perfection. 

It  consists  of  various  coverings  enclosing  an 
embryo,  being  the  granule  of  pollen  deposited 
there,  which  is  the  rudiment  of  a  future  plant. 

The  seed  is  nourished  by  the  same  means  as 
the  fruit ;  and,  like  it,  will  be  more  or  less  per- 
fectly formed,  according  to  the  abundance  of 
its  nutriment. 


52  SEED. 

The  plant  developed  from  the  embryo  in  the 
seed,  will  be  in  all  essential  particulars  like  its 
parent  species. 

Unless  its  nature  has  been  changed  by  hy- 
bridising. 

But  although  it  will  certainly,  under  ordinary 
circumstances,  reproduce  its  species,  it  will  by 
no  means  uniformly  reproduce  the  particular 
variety  by  which  it  was  borne. 

So  that  seeds  are  not  the  proper  means  of 
propagating  varieties. 

Nevertheless,  in  annual  or  biennial  plants,  no 
means  can  be  employed  for  propagating  a 
variety,  except  the  seeds ;  and  yet  the  variety 
is  preserved. 

This  is  accomplished  solely  by  the  great  care 
of  the  cultivator,  and  happens  thus. 

Although  a  seed  will  not  absolutely  propa- 
gate the  individual,  yet  as  a  seed  will  partake 
more  of  the  nature  of  its  actual  parent  than  of 
any  thing  else,  its  progeny  may  be  expected, 
as  really  happens,  to  resemble  the  variety  from 
which  it  sprung,  more  than  any  other  variety 
of  its  species. 

Provided  its  purity  have  not  been  contami- 
nated by  the  intermixture  of  other  varieties. 

Bv  a  careful  eradication  of  all  the  varieties 


SEED.  53 

from  the  neighborhood  of  that  from  which  seed 
is  to  be  saved,  by  taking  care  that  none  but  the 
most  genuine  forms  of  a  variety  are  preserved 
as  seed-plants ;  and  by  compelling  by  trans- 
plantation a  plant  to  expend  all  its  accumulated 
sap  in  the  nourishment  of  its  seeds,  instead  of 
in  the  superabundant  production  of  foliage,  a 
crop  of  seed  may  be  procured,  the  plants  pro- 
duced by  which  will,  in  a  great  measure,  have 
the  peculiar  properties  of  the  parent  variety. 

By  a  series  of  progressive  seed-savings  upon 
the  same  plan,  plants  will  be  at  length  obtained, 
in  which  the  habits  of  the  individual  have  be- 
come as  it  were  fixed,  and  capable  of  such 
exact  reproduction  by  seed,  so  as  to  form  an  ex- 
ception to  the  general  rule ;  as  in  Turnips, 
Radishes,  &c. 

But  if  the  least  neglect  occurs  in  taking  the 
necessary  precautions  to  ensure  a  uniform  crop 
of  seed,  possessing  the  new  fixed  properties, 
the  race  becomes  deteriorated,  in  proportion  to 
the  want  of  care  that  has  occurred,  and  loses 
its  characters  of  individuality. 

In  all  varieties  those  seeds  may  be  expected 

to  preserve   their  individual    characters   most 

distinctly  which  have  been  the  best  nourished  ; 

it  is,  consequently,  those  which  should  be  se- 

5* 


54  SEED. 

lected  in  preference  for  raising  new  plants, 
from  which  seed  is  to  be  saved. 

When  plants  have  been  propagated  for  a 
series  of  years  by  suckers  alone,  which  are  ad- 
ventitious buds  arising  from  the  root,  their  power 
of  producing  seed  seems  somewhat  impaired, 
this  is  the  case  with  many  herbaceous  plants 
and  bulbs,  but  if  a  single  seed  be  found  by 
which  to  raise  a  new  plant,  the  faculty  of  bear- 
ing seed  becomes  renewed. 

When  seeds  are  first  ripened,  their  embryo 
is  a  mass  of  cellular  substance,  containing 
starch,  fixed  carbon,  or  other  solid  matter  in 
its  cavities;  and  in  this  state  it  will  remain 
until  fitting  circumstances  occur  to  call  it  into 
active  life. 

These  fitting  circumstances  are,  a  tempera- 
ture above  freezing  point,  a  moist  medium, 
(earth)  darkness,  and  exposure  to  air. 

It  then  absorbs  the  moisture  of  the  medium 
in  which  it  lies,  decomposes  water  from  which  it 
inhales  oxygen,  and  undergoes  certain  chemical 
changes ;  its  vital  powers  cause  one  extremity 
of  it  to  ascend  for  the  purpose  of  finding  light,  of 
decomposing  its  carbonic  acid,  by  parting  with 
its  accumulated  oxygen,  and  forming  leaves  and 
branches,  and  the  other  extremity  to  descend  for 


SEED.  55 

the  purpose  of  finding  a  constant  supply  of  crude 
nutriment  and  becoming  roots. 

Unless  these  conditions  are  maintained,  seeds 
cannot  germinate ;  and,  consequently,  an  ex- 
])osure  to  light  is  fatal  to  their  embryo,  because 
oxygen  will  not  be  absorbed  in  sufficient  quan- 
tity to  stimulate  the  vital  powers  of  the  embryo 
into  action,  for  the  purpose  of  parting  with  it 
again,  by  the  decomposition  of  the  carbonic 
acid  that  has  been  formed  during  its  accumu- 
lation. 

The  length  of  time  which  seeds  preserve 
their  power  of  growing,  or  vitality  as  it  is  call- 
ed, differs  in  different  plants.  Some  lose  their 
vitality  in  a  single  year,  others  preserve  it  for 
many  years  —  the  best  authenticated  account 
of  this  latter  power  is  of  some  raspberry  trees 
now  growing  in  the  garden  of  the  Horticultural 
Society  of  London,  which  were  raised  from 
seeds  taken  out  of  the  stomach  of  a  skeleton 
found  in  one  of  the  tumuli  or  ancient  tombs  at 
Dorchester  England,  thirty  feet  helow  the  sur- 
face. With  the  skeleton  were  found  some  coins 
of  the  Emperor  Hadrian  —  so  that  they  must 
have  been  sixteen  or  seventeen  hundred  years 
old.  The  raspberry  has  also  vegetated  from 
seeds  taken  from  raspberry  jam,  in  this  case 


66  SEED. 

they  must  have  borne  the  heat  of  cooking  for  a 
length  of  time.  This  plant,  as  is  well  known, 
is  a  native  of  the  colder  parts  of  this  continent ; 
the  integuments  or  coverings  of  the  seed  must 
therefore  have  been  formed  with  wonderful 
powers  of  protection  against  extremes  of  heat, 
cold,  and  age. 

Pine  seeds  and  many  others  vegetate  very 
rapidly  in  lime  just  slacked.  This  action  produ- 
ces warmth,  and  the  lime  immediately  attracts 
the  excess  of  carbonic  acid  from  the  seed,  this, 
as  before  observed,  being  one  of  the  chief  con- 
ditions of  vegetating. 

The  business  of  saving  seed  for  gardens  as 
a  trade,  is  quite  new  in  this  country,  and  many 
hundred  dollars  are  annually  expended  in  im- 
porting seeds  from  Europe.  The  vitality  of 
some  is  injured  by  the  voyage. 

It  will  be  seen  by  the  foregoing  information 
that  it  would  be  useless  to  compete  with  Euro- 
pean seedsmen,  unless  this  branch  were  follow- 
ed as  a  business,  so  much  attention,  so  many 
precautions  are  requisite  to  procure  true,  full, 
and  plump  seeds  of  vegetables  or  flowers.  But 
it  is  equally  certain  if  this  attention  were  paid  so 
as  to  ensure  an  infallible  character  after  proper 
trials  to  the  seisds  grown,  that  the  alpine  purity 


SAP.  57 

of  the  atmosphere,  the  quantity  and  intensity 
of  solar  light,  by  ripening  all  the  juices,  and 
particularly  the  pollen  of  plants,  would  enable 
the  seed-growers  of  this  country  to  excel  by  far 
those  of  Europe. 

But  unless  done  thoroughly,  it  is  no  use  to 
make  the  attempt,  as  a  grower  once  disap- 
pointed in  the  quality  of  his  seed  will  scarcely 
ever  try  the  same  source  again. 


Sap. 

The  fluid  matter  which  is  absorbed  either 
from  the  earth  or  from  the  air  is  called  sap. 

When  it  first  enters  a  plant  it  consists  of 
water  holding  certain  principles,  especially 
carbonic  acid,  in  solution. 

These  principles  chiefly  consist  of  animal  or 
vegetable  matter  in  a  state  of  decomposition, 
and  salts,  and  are  energetic  in  proportion  to 
their  solubility,  or  tendency  to  form  carbonic 
acid  by  combining  with  the  oxygen  of  the  air. 

Sap  soon  afterwards  acquires  the  nature  of 
mucilage  or  sugar,  and  subsequently  becomes 
still  further  altered  by  the  admixture  of  such 
soluble  matter  as  it  receives  in  passing  in  its 


58  SAP. 

route  through  the  alburnum  or  newly  formed 
woody  tissue. 

When  it  reaches  the  vicinity  of  the  leaves  it 
is  attracted  into  them,  and  there,  having  been 
exposed  to  light  and  air,  is  converted  into  the 
secretions  peculiar  to  the  species. 

It  finally,  in  its  altered  state,  sinks  down  the 
bark,  whence  it  is  given  off  laterally  by  the 
medullary  rays,  and  is  distributed  through  the 
system. 

The  cause  of  the  motion  of  the  sap  is  the  at- 
traction of  the  leaf-buds  and  leaves. 

The  leaf-buds,  called  into  growth  by  the 
combined  action  of  the  increasing  temperature 
and  light  of  spring,  decompose  their  carbonic 
acid,  and  attract  fluid  from  the  tissue  imme- 
diately below  them ;  the  space  so  caused  is 
filled  up  by  fluid  again  attracted  from  below, 
and  thus  a  motion  gradually  takes  place  in  the 
sap  from  one  extremity  to  the  other. 

Consequently  the  motion  of  the  sap  takes 
place  first  in  the  branches  and  last  in  the 
roots. 

For  this  reason  a  branch  of  a  plant  sub- 
jected to  a  high  temperature  in  winter  will 
grow  while  its  stem  is  exposed  to  a  very  low 
temperature. 


SAP.  59 

But  growth  under  such  circumstances  will 
not  be  long  maintained,  unless  the  roots  are 
secured  from  the  reach  of  frost :  for,  if  frozen 
they  cannot  act,  and  will,  consequently,  be  un- 
able to  replace  the  sap  of  which  the  stem  is 
emptied  by  the  attraction  of  the  buds  converted 
into  branches,  and  by  the  perspiration  of  the 
leaves. 

Whatever  tends  to  condense  the  sap,  such 
as  a  dry  and  heated  atmosphere,  or  an  inter- 
ruption of  its  rapid  flow,  or  a  great  decomposi- 
tion of  carbonic  acid  by  full  exposure  to  light, 
has  the  property  of  causing  excessive  vigor 
to  be  diminished,  and  flower-buds  to  be  pro- 
duced. 

While,  on  the  other  hand,  whatever  tends  to 
dilute  the  sap,  such  as  the  free  and  rapid  circu- 
lation of  it,  a  damp  atmosphere,  or  a  great  ac- 
cumulation of  oxygen  in  consequence  of  the 
imperfect  decomposition  of  carbonic  acid,  has 
the  property  of  causing  excessively  rapid 
growth,  and  an  exclusive  production  of  leaf- 
buds. 

Condensed  or  accumulated  sap  is,  therefore, 
a  great  cause  of  fertility. 

And  thin  fluid,  not  being  elaborated,  is  a 
great  cause  of  sterility. 


60  AIR    AND    LIGHT. 

The  conversion  of  sap  into  different  kinds 
of  secretion  is  effected  by  the  combined  action 
of  Air,  Light,  and  Temperature. 

Mr.  Knight  is  of  opinion,  founded  like  all  his 
opinions,  on  well  conducted  experiments,  that 
the  motion  given  to  plants  by  the  wind,  enables 
their  fluids  to  circulate  more  freely  and  is  thus 
beneficial. 

Air  and  Light. 

When  an  embryo  plant  is  formed  within  its 
integuments,  it  is  usually  colorless,  or  nearly 
so  ;  but,  as  soon  as  it  begins  to  grow,  that  part 
which  approaches  the  light  (the  stem)  becomes 
colored,  while  the  opposite  extremity  (the  root) 
remains  colorless. 

The  parts  exposed  to  the  air  absorb  oxygen 
at  night,  absorb  carbonic  acid  and  part  with 
oxygen  again  in  daylight ;  and  thus  in  the  day- 
time purify  the  air,  and  render  it  fit  for  the  re- 
spiration of  man. 

The  intensity  of  this  latter .  operation  is  in 
proportion  to  the  intensity  of  solar  light  to 
which  leaves  are  directly  exposed. 

Its  cause  is  the  decomposition  of  carbonic 
acid,  the  extrication  of  oxygen,  and  the  acquisi- 


AIR    AND    LIGHT.  61 

tioii  by  the  plant  of  carbon  in  a  solid  state ; 
from  which,  modified  by  the  peculiar  vital 
actions  of  species,  color  and  secretions  are  sup- 
})oscd  to  result. 

For  it  is  found  that  the  intensity  of  color  and 
the  quantity  of  secretions  are  in  proportion  to 
the  exposure  to  light  and  air,  as  is  shown 
by  the  deeper  color  of  the  upper  side  of 
leaves,  &c. 

And  by  the  fact,  that  if  plants  be  grown  in 
air  from  which  light  is  excluded,  neither  color 
nor  secretions  are  formed,  as  is  exemplified  in 
blanched  vegetables ;  which,  if  even  naturally 
poisonous,  may,  from  want  of  exposure  to  light, 
become  wholesome,  as  Celery. 

When  any  color  appears  in  parts  developed 
in  the  dark  it  is  generally  caused  by  the  absorp- 
tion of  such  coloring  matter  as  pre-existed  in 
the  root  or  other  body  from  wliich  the  blanched 
shoot  proceeds,  as  in  some  kinds  of  Rhubarb 
when  forced. 

Or  by  the  deposition  of  coloring  matter  form- 
ed by  parts  developed  in  light,  as  in  the  subter- 
ranean roots  of  Beet,  Carrots,  &c. 

What  is  true  of  color  is  also  true  of  flavor, 
which  equally  depends  upon  light  for  its  ex- 
istence ;  because  flavor  is  produced  by  chemi- 
6 


62  AIR    A^•D    LIGHT. 

cal  alterations  in  the  sap  caused  by  exposure  to 
light. 

The  same  thing  occurs  in  regard  to  nutritive 
matter,  which  in  like  manner  is  formed  by  the 
exposure  of  leaves  to  light.  Thus  the  Potato 
when  forced  in  dark  houses  contains  no  more 
farinaceous  matter  than  previously  existed  in 
the  original  tuber  ;  but  acquires  it  in  abundance 
when  placed  in  the  light,  and  deposits  it  in  pro- 
portion as  it  is  influenced  by  light  and  air. 
Thus,  also,  if  Peaches  are  grown  in  wooden 
houses,  at  a  distance  from  the  light,  they  will 
form  so  little  nuti'itive  matter  as  to  be  unable 
to  support  a  crop  of  fruit,  the  greater  part  of 
which  will  fall  off.  And  for  a  similar  reason 
it  is  only  the  outside  shoots  of  standard  fruit 
trees  that  bear  fruit.  Considerations  of  this 
kind  form  in  part  the  basis  of  pruning  and 
training. 

Light  is  the  most  powerful  stimulus  tliat  can 
be  employed  to  excite  the  vital  actions  of  plants, 
and  its  energy  is  in  proportion  to  its  intensity  ; 
so  that  the  direct  rays  of  the  sun  will  produce 
much  more  powerful  effects  than  the  diffused 
light  of  day. 

Hence,  if  buds,  that  are  very  excitable  are 
placed  in  the  shade,  their  excitability  will  be 
checked. 


AIR    AND    LIGHT.  63 

And  if  buds  that  are  very  torpid  are  exposed 
to  direct  light,  they  will  be  stimidated  into 
action. 

So  that  what  parts  of  a  tree  shall  first  begin 
to  grow  in  the  spring  may  be  determined  at  the 
will  of  the  cultivator. 

This  is  the  key  to  some  important  practices 
in  forcing. 

This  should  also  cause  attention  to  be  paid 
to  shading  buds  from  the  direct  rays  of  the  sun 
in  particular  cases :  as  in  that  of  cuttings, 
whose  buds,  if  too  rapidly  excited,  might  ex- 
haust their  only  reservoir  of  sap,  the  stem, 
before  new  roots  were  formed  to  repair  such 
loss. 

As  plants  derive  an  essential  part  of  their 
food  from  the  air  by  the  action  of  light,  it  fol- 
lows that  in  glass-houses  those  which  admit  the 
greatest  portion  of  light  are  the  best  adapted  for 
purposes  of  cultivation. 

And  as  it  has  been  found  by  experiment, 
that  light  passes  more  freely  through  a  cur- 
vilinear than  through  a  plane  roof,  and  through 
glass  forming  an  acute  angle  with  the  horizon 
than  through  perpendicular  glass,  it  follows  that 
a  curvilinear  roof  is  best,  and  a  plane  roof  with 
glass  perpendicular  sides  the  worst  adapted  to 
the  purposes  of  the  cultivator. 


64  PERSPIRATION. 

For  the  same  reason  common  green  glass  is 
less  fitted  for  glazing  forcing-houses  than  white 
crown  glass. 

Poisonous  gases  in  very  minute  quantities 
act  upon  vegetation  with  great  energy.  A  ten- 
thousandth  part  of  sulphurous  acid  gas  is  quickly 
fatal  to  the  life  of  plants  ;  and  hence  the  danger 
of  flues  heated  by  coal  fires,  and  the  impossi- 
bility of  making  many  species  grow  in  the 
vicinity  of  houses  heated  by  coal  fires,  or  in 
large  towns. 

Heating  by  hot  water  is  now  so  well  under- 
stood, and  so  simplified  by  the  method  of  first 
heating  the  air  in  a  large  reservoir,  or  air  cham- 
ber, from  which  it  circulates  to  any  required 
part,  either  of  a  green  house  or  dwelling  house, 
that  no  one  erecting  a  glass  structure  for  plants 
would  now  think  of  heating  on  the  old  princi- 
ple of  the  fire  flue. 

Perspiration. 

It  is  not,  however,  exclusively  by  the  action 
of  light  and  air  that  the  nature  of  sap  is  al- 
tered. Evaporation  from  the  leaves  is  con- 
stantly going  on  during  the  growth  of  a  plant, 
and  sometimes  is  so  copious,  that  an  individual 


PERSPIRATION.  65 

will   perspire  its  own  weight  of  water  in  the 
course  of  24  hours. 

The  loss  thus  occasioned  by  the  leaves  is 
supplied  by  crude  fluid,  a  large  portion  of 
which  is  water,  absorbed  by  the  roots,  and  con- 
veyed up  the  stem  with  great  rapidity. 

The  consequence  of  such  copious  perspira- 
tion is  the  separation  and  solidification  of  the 
carbonised  matter  that  is  produced  for  the  pe- 
culiar secretions  of  a  species. 

For  the  maintenance  of  a  plant  in  health,  it 
is  indispensable  that  the  supply  of  fluid  by  the 
roots  should  be  continual  and  uninterrupted. 

If  any  thing  causes  perspiration  to  take  place 
faster  than  it  can  be  counteracted  by  the  ab- 
sorption of  fluid  from  the  earth,  plants  will  be 
dried  up  and  perish. 

Such  causes  are,  destruction  of  spongioles, 
an  insufficient  quantity  of  fluid  in  the  soil,  an 
exposure  of  the  spongioles  to  occasional  dry- 
ness, and  a  dry  atmosphere. 

The  most  ready  means  of  counteracting  the 
evil  consequences  of  an  imperfect  action  of  the 
roots  is  by  preventing  or  diminishing  evapora- 
tion. 

This  is  to  be  effected  by  rendering  the  atmos- 
phere extremely  humid. 
6* 


66  PERSPIRATION. 

Thus,  in  curvilinear  iron  hot-houses,  in  which 
the  atmosphere  becomes  so  dry  in  consequence 
of  the  heat  that  plants  perish,  it  is  necessary 
that  the  air  should  be  rendered  extremely  hu- 
mid, by  throwing  water  upon  pavement,  or  by 
introducing  steam. 

And  in  transplantation  in  dry  weather,  ever- 
greens, or  plants  in  leaf,  often  die,  because  tiie 
spongioles  are  destroyed,  or  so  far  injured  in 
the  operation  as  to  be  unable  to  act,  while  the 
leaves  never  cease  to  perspire. 

The  greater  certainty  of  transplanting  plants 
that  have  been  growing  in  pots  is  from  this  lat- 
ter circumstance  intelligible  ; 

While  the  utility  of  putting  cuttings  or  newly 
transplanted  seedlings  into  a  shady  damp  at- 
mosphere, is  explained  by  the  necessity  of  les- 
sening evaporation  produced  by  solar  light. 

The  admission  of  air  or  ventilation,  as  it  is 
called,  is  not  generally  well  understood  by  gar- 
deners. Much  light  has  been  thrown  on  this 
subject,  since  the  invention  of  the  air  tight 
boxes  of  Mr.  Ward,  in  which,  owing  to  the 
total  exclusion  of  currents  of  air  (ventilation) 
the  evaporation  from  the  surface  of  the  earth 
and  plants  is  constant,  according  to  the  heat, 


I'KRSPinATION.  67 

and  the  atmosphere  is  thus  kept  uniformly 
moist,  not,  as  in  green  houses,  moist  all  night 
and  dried  by  ventilation  all  day.  The  only 
way  of  growing  plants  to  perfection  in  rooms, 
is  in  these  Ward's  boxes  —  and  the  plants 
in  most  glass  structures  would  thrive  better 
with  much  less  ventilation.  The  greater  the 
heat  the  more  moisture  is  required.  The 
custom  of  gardeners  seems  preposterous,  to 
deluge  the  floors  of  green  houses  with  water 
to  create  a  damp  atmosphere,  and  then  ven- 
tilate freely,  which  dries  it  up.  This  capricious 
change  is  very  injurious  to  plants. 

It  is  thought  by  some  geologists,  that  the 
gigantic  growth  of  the  plants  of  former  ages, 
of  which  such  beautiful  specimens  are  daily 
discovered  in  coal  mines,  was  favored  by  the 
extreme  heat  and  moisture  with  which  the  sur- 
face of  the  globe  was  then  covered. 

Mr.  Knight,  in  a  forcing  house  devoted  to 
experiment,  never  gave  air  to  his  grapes  until 
nearly  ripe,  even  in  hottest  and  brightest 
weather,  farther  than  just  necessaiy  to  prevent 
the  leaves  being  destroyed  by  excess  of  heat, 
and  employed  very  little  fire  heat.  Many  hot 
houses  are  now  built  in  Europe  without  any 
means  of  ventilation.     It  must  be  remembered. 


68  CUTTINGS. 

however,  that  dampness,  unaccompanied  by- 
warmth  and  light,  will  produce  fungi  and  all 
their  injurious  concomitants. 

Cuttings. 

When  a  separate  portion  of  a  plant  is  caused 
to  produce  new  roots  and  branches,  and  to  in- 
crease an  individual,  it  is  a  cutting. 

Cuttings  are  of  two  sorts,  —  cuttings  properly 
so  called,  and  eyes. 

A  cutting  consists  of  an  internodium,  (space 
between  bud  and  bud)  or  a  part  of  one,  whh  its 
nodus  and  leaf-bud. 

When  the  internodium  is  plunged  in  the 
earth  it  attracts  fluid  from  the  soil,  and  nour- 
ishes the  bud  until  it  can  feed  itself 

The  bud,  feeding  at  first  upon  the  matter  in 
the  internodium,  gradually  elongates  upwards 
into  a  branch,  and  sends  organised  matter 
downwards,  which  becomes  roots. 

As  soon  as  it  has  established  a  communica- 
tion with  the  soil,  it  becomes  a  new  individual, 
exactly  like  that  from  which  it  was  taken. 

As  it  is  the  action  of  the  leaf-buds  that  causes 
growth  in  a  cutting,  it  follows  that  no  cutting 
without  a  leaf-bud  will  grow  ; 


CUTTINGS.  69 

Unless  the  cutting  has  great  vitality  and 
power  of  forming  adventitious  leaf-buds,  which 
sometimes  happens. 

An  eye  is  a  leaf-bud  without  an  internodium. 

It  only  differs  from  a  cutting  in  having  no 
reservoir  of  food  on  which  to  exist,  and  in 
emitting  its  roots  immediately  from  the  base  of 
the  leaf-bud  mto  the  soil. 

As  cuttings  will  very  often,  if  not  always, 
develope  leaves  before  any  powerful  connec- 
tion is  formed  between  them  and  the  soil, 
they  are  peculiarly  liable  to  suffer  from  perspi- 
ration. 

Hence  the  importance  of  maintaining  their 
atmosphere  in  an  uniform  state  of  humidity,  as 
is  effected  by  putting  bell  or  other  glasses  over 
them. 

In  this  case,  however,  it  is  necessary  that 
if  air-tight  covers  are  employed,  such  as  bell 
glasses,  they  should  be  from  time  to  time  re- 
moved and  replaced,  for  the  sake  of  getting 
rid  of  excessive  humidity. 

Layers  differ  from  cuttings  in  nothing  ex- 
cept that  they  strike  root  into  the  soil  while  yet 
adhering  to  the  parent  plant. 

Whatever  is  true  of  cuttings  is  true  of  layers, 
except  that  the  latter  are  not  liable  to  suffer  by 


70  CUTTINGS. 

evaporation,  because  of  their  communication 
with  the  parent  plant. 

As  cuttings  strike  roots  into  the  earth  by  the 
action  of  leaves  or  leaf-buds,  it  might  be  sup- 
posed that  they  will  strike  most  readily  when 
the  leaves  or  leaf-buds  are  in  their  greatest 
vigor. 

Nevertheless,  this  power  is  controlled  so 
much  by  the  peculiar  vital  powers  of  different 
species,  and  by  secondary  considerations,  that 
it  is  impossible  to  say  that  this  is  an  absolute 
rule. 

Thus  Dahlias  and  other  herbaceous  plants 
will  strike  root  freely  when  cuttings  are  very 
young  ;  and  Heaths,  Azaleas,  and  other  hard 
wooded  plants,  only  when  the  wood  has  just 
begun  to  harden. 

The  former  is,  probably,  owing  to  some  spe- 
cific vital  excitability,  the  force  of  which  we 
cannot  appreciate  ;  the  latter  either  to  a  kind 
of  torpor,  which  seems  to  seize  such  plants 
when  their  tissue  is  once  emptied  of  fluid,  or  to 
a  natural  slowness  to  send  downwards  woody 
matter,  whether  for  wood  or  not,  which  is  the 
real  cause  of  their  wood  being  harder. 

If  ripened  cuttings  are  upon  the  whole  the 
most  fitted  for  multiplication,  it  is  because  their 


CUTTINGS.  71 

tissue  is  less  absorbent  than  when  younger,  and 
that  they  are  less  likely  to  suffer  from  either 
repletion  or  evaporation. 

For  to  gorge  tissue  with  food,  before  leaves 
are  in  action  to  decompose  and  assimilate  it,  is 
as  prejudicial  as  to  empty  tissue  by  the  action 
of  leaves,  before  spongioles  are  prepared  to 
replenish  it. 

For  this  reason  pure  silex,  in  which  no  stim- 
ulating substances  are  contained  (silver  sand,) 
is  the  best  adapted  for  promoting  the  rooting  of 
cuttings  that  strike  with  difficulty. 

And  for  the  same  reason  cuttings  with  what 
gardeners  call  a  heel  to  them,  or  a  piece  of 
the  older  wood,  strike  root  more  readily  than 
such  as  are  not  so  protected.  The  greater 
age  of  the  tissue  of  the  heel  renders  it  less 
absorbent  than  tissue  that  is  altogether  newly 
formed. 

It  is  to  avoid  the  bad  effect  of  evaporation 
that  a  proportion  of  the  leaves  are  usually  re- 
moved from  a  cutting,  when  it  is  first  pre- 
pared. 

The  method  of  striking  cuttings  in  double 
pots,  the  outer  filled  with  earth  in  which  the 
cuttings  are  placed  with  the  ends  inserted  in 
the  earth  touching  the  sides  of  the  inner  one, 


72  SCIONS. 

which  is  kept  filled  with  water  has  for  the 
above  reason  been  attended  with  success. 

The  directions  for  propagating  by  cuttings  in 
European  publications,  generally  state  the 
month  for  placing  them  in  the  earth  ;  these 
directions  would  be  apt  to  mislead  in  this  coun- 
try, where  the  difference  of  temperature  ripens 
wood  at  a  different  period. 

Cuttings  will  strike  at  any  period  of  the  year 
when  the  young  wood  is  sufficiently  ripe  and 
the  plant  is  continuing  its  growth,  but  not  when 
it  is  in  a  state  of  rest. 

Scions. 

A  scion  is  a  cutting  which  is  caused  to  grow 
upon  another  plant,  and  not  in  earth. 

Scions  are  of  two  sorts,  scions  properly  so 
called,  and  huds. 

Whatever  is  true  of  cuttings  is  true  also  of 
scions,  all  circumstances  being  equal. 

When  a  scion  is  fitted  on  to  another  plant, 
it  attracts  fluid  from  it  for  the  nourishment  of 
its  leaf-buds  until  they  can  feed  themselves. 

Its  buds  thus  fed  gradually  grow  upwards 
into  branches,  and  send  woody  matter  down- 
wards, which  is  analogous  to  roots. 


SCIONS.  73 

At  the  same  time  the  cellular  substance  of 
the  scion  and  its  stock  adheres  so  as  to  form  a 
complete  organic  union. 

The  woody  matter  descending  from  the  buds 
passes  through  the  cellular  substance  into  the 
stock,  where  it  occupies  the  same  situation  as 
would  have  been  occupied  by  woody  matter 
supplied  by  buds  belonging  to  the  stock  itself. 

Once  united,  the  scion  covers  the  wood  of 
the  stock  with  new  wood,  and  causes  the  pro- 
duction of  new  roots. 

But  the  character  of  the  woody  matter  sent 
down  by  the  scion  over  the  wood  of  the  stock 
being  determined  by  the  cellular  tissue,  which 
has  exclusively  a  horizontal  development,  it 
follows  that  the  wood  of  the  stock  will  always 
remain  apparently  the  same,  although  it  is  fur- 
nished by  the  scion. 

While  the  preparations  of  the  juices  being 
effected  by  the  leaves  of  the  scion,  the  produce 
thereof  will  be  the  same  as  the  species  from 
which  the  scion  was  taken. 

Some  scions  will  grow  upon  a  stock  without 
being  able  to  transmit  any  woody  matter  into 
it ;  as  some  Cacti,  which  have  only  a  small 
central  development  of  woody  tissue. 

When  this  happens,  the  adhesion  of  the  two 
7 


74  SCIONS. 

takes  place  by  the  cellular  substance  only,  and 
the  union  is  so  imperfect  that  a  slight  degree  of 
violence  suffices  to  dissever  them. 

And  in  such  cases  the  buds  are  fed  by  their 
woody  matter,  which  absorbs  the  ascending  sap 
from  the  stock  at  the  point  where  the  adhesion 
has  occurred ;  and  the  latter,  never  augmenting 
in  diameter,  is  finally  overgrown  by  the  scion. 
When,  in  such  instances,  the  communication 
between  the  stock  and  the  scion  is  so  much  in- 
terrupted that  the  sap  can  no  longer  ascend  with 
sufficient  rapidity  into  the  branches,  the  latter 
die ;  as  in  many  Peaches. 

This  incomplete  union  between  the  scion  and 
its  stock  is  owing  to  some  constitutional  or  or- 
ganic difference  in  the  two. 

Therefore  care  should  be  taken  that  when 
plants  are  grafted  on  one  another  their  constitu- 
tion should  be  as  nearly  as  possible  identical. 

As  adhesion  of  only  an  imperfect  nature 
takes  place  when  the  scion  and  stock  are,  to  a 
certain  degree,  dissimilar  in  constitution,  so  will 
no  adhesion  whatever  occur  when  their  consti- 
tutional differences  are  very  decided. 

Hence  it  is  only  species  very  nearly  allied  in 
nature  that  can  be  grafted  on  each  other. 

As  only  similar  tissues  will  unite,  it  is  neces- 
sary in  applying  a  scion  to  the  stock  that  similar 


SCIONS, 


75 


parts  sliould  be  carefully  adapted  to  each  other  ; 
as  bark  to  bark,  cambium  to  cambium,  and  al- 
burnum to  alburnum. 

The  second  is  more  especially  requisite,  be- 
cause it  is  through  the  cambium  that  the  woody 
matter  sent  downwards  by  the  buds  must  pass ', 
and  also  because  cambium  itself,  being  organ- 
ising matter  in  an  incipient  state,  will  more 
readily  form  an  adhesion  than  any  other  part. 
The  same  principles  apply  to  huds^  which  are 
to  scions  precisely  what  eyes  are  to  cuttings. 

Inarching  is  the  same  with  reference  to 
grafting  that  layering  is  with  reference  to 
striking  by  cuttings. 

It  serves  to  maintain  the  vitality  of  a  scion 
until  it  can  form  an  adhesion  with  its  stock; 
and  must  be  considered  the  most  certain  mode 
of  grafting. 

It  is  probable  that  every  species  of  flowering 
plant,  without  exception,  may  be  multiplied  by 
grafting. 

Nevertheless,  there  are  many  species  and 
even  tribes  that  never  have  been  grafted. 

It  has  been  found  that  in  the  Vine  and  the 
Walnut  this  difficulty  can  be  overcome  by  atten- 
tion to  their  peculiar  constitutions ;  and  it  is 
probable  that  the  same  attention  will  remove 
supposed  difficulties  in  the  case  of  other  species. 


76  SCIONS. 

It  is  certain  that  scions  thrive  better  on  some 
stocks  even  of  the  same  species  than  others, 
and  that  this  depends  somewhat  on  the  soil  in 
which  the  stock  grows ;  this  is  a  subject  how- 
ever on  which  there  has  been  so  much  discus- 
sion, and  on  which  practical  experience  has  yet 
so  much  to  develop,  that  no  certain  general 
rules  can  be  laid  down,  particularly  in  this 
country. 

From  what  has  been  said  on  perspiration  it 
seems  that  the  practice  of  budding  on  the 
northern  side  of  stems  must  be  correct. 

Mr.  Knight  often  applied  two  ligatures  to  his 
buddings  on  Peach  trees,  one  above  the  bud 
across  the  transverse  incision,  the  other  below, 
this  last  was  taken  off  as  soon  as  the  bud  ad- 
hered, the  upper  one  was  left  on,  thus  obstruct- 
ing the  flow  of  the  sap  upwards  and  throwing 
it  into  the  bud,  which  then  vegetated  early  and 
produced  blossoms  the  following  spring.  As 
soon  as  the  new  shoot  had  attained  about  four 
inches  in  length  the  upper  bandage  was  re- 
moved and  the  sap  suffered  to  flow  freely.  By 
following  this  practice  with  roses,  and  by  judi- 
cious heading  down,  I  have  obtained  very  large 
and  healthy  bushes  on  the  top  of  a  single 
straight  stem  the  third  year. 


ttiansplantatton.  77 

Transplantation. 

Transplantation  consists  in  removing  a  plant 
from  the  soil  in  which  it  is  growing  to  some 
other  soil. 

If  in  the  operation  the  plant  is  torpid,  and 
its  spongioles  uninjured,  the  removal  will  not 
be  productive  of  any  interruption  to  the  pre- 
vious rate  of  growth. 

And  if  it  is  growing,  or  evergreen,  and  the 
spongioles  are  uninjured,  the  removal  will  pro- 
duce no  further  injury  than  may  arise  from  the 
temporary  suspension  of  the  action  of  the  spon- 
gioles, and  the  noncessation  of  perspiration 
during  the  operation. 

So  that  transplantation  may  take  place  at  all 
seasons  of  the  year,  and  under  all  circumstan- 
ces, provided  the  spongioles  are  uninjured. 

This  applies  to  the  largest  trees  as  well  as  to 
the  smallest  herbs. 

But  as  it  is  impossible  to  take  plants  out  of  the 
earth  without  destroying  or  injuring  the  spongio- 
les, the  evil  consequences  of  such  accidents  must 
be  remedied  by  the  hindrance  of  evaporation. 

Transplantation  should  therefore  take  place 
only  when  plants  are  torpid,  and  when  their 
respiratory  organs  (leaves)  are  absent ;  or,  if 


78  TRANSPLANTATION. 

they  never  lose  those  organs,  as  evergreens, 
only  at  seasons  when  the  atmosphere  is  peri- 
odically charged  with  humidity  for  some  con- 
siderable time. 

Old  trees  in  which  the  roots  are  much  in- 
jured form  new  ones  so  slowly,  that  they  are 
very  liable  to  be  exhausted  of  sap  by  the  ab- 
sorption of  their  very  numerous  young  buds 
before  new  spongioles  can  be  formed. 

The  amputation  of  all  their  upper  extremities 
is  the  most  probable  prevention  of  death ;  but 
in  most  cases  injury  of  their  roots  is  without  a 
remedy. 

Plants  in  pots  being  so  circumstanced  that 
the  spongioles  are  protected  from  injury,  can, 
however,  be  transplanted  at  all  seasons,  without 
any  dangerous  consequences. 

On  the  subject  of  transplantation  much  dif- 
ference of  opinion  exists,  particularly  as  to  the 
most  favorable  period  of  performing  this  opera- 
tion. Lindley  has  several  pages  of  argument 
in  favor  of  transplanting  in  the  autumn  as  soon 
as  the  fall  of  the  leaf  indicates  a  recession  of 
the  sap,  and  of  course  a  stillness  of  vegetation. 
I  have  planted  many  trees  in  England  and  agree 
with  him  that  November  and  December  are  the 
most  preferable  months  —  but  it  is  not  clear  that 
the  same  arguments  are  true  in  this  climate. 


TRANSPLANTATION.  79 

Trees  are  not  generally  taken  up  with  the 
same  care  here  as  there,  and  even  if  they  were, 
the  roots  and  small  fibres  are  still  usually  much 
wounded  and  injured.  If  transplanted  in  Sep- 
tember or  October  just  previous  to  the  frost 
entering  the  ground,  there  is  not  time  for  these 
injuries  to  heal  before  the  action  of  the  severe 
frosts  of  our  winters,  which  is  sure  to  penetrate 
to  them  as  the  earth  is  loosened  all  round  by 
transplanting;  this  action  of  the  frost  on  the 
lacerated  roots  must  of  course  be  in  many 
cases  fatal.  Again  in  March  and  April,  par- 
ticularly the  former,  the  most  drying  winds  of 
the  year  prevail  in  England,  which  is  unfavor- 
able to  transplantation  as  increasing  the  evapo- 
ration. Here  the  earth  in  those  months  is  usually 
extremely  moist  from  the  melting  of  the  snow, 
&c.  Hence  it  would  appear  that  these  months 
are  more  favorable  for  the  operation  of  trans- 
plantation here  than  in  England  —  and  it  seems 
probable  that  there  is  less  chance  of  failure  in 
this  climate  by  transplanting  early  in  the  spring 
than  in  the  autumn;  still  I  have  now  before 
me  several  trees  transplanted  in  November 
which  have  stood  this  severe  winter,  and  are 
now  in  full  leaf  and  beauty.  Also  the  spon- 
gioles  of  the  roots  of  trees  transplanted  in 
autumn  are  better  settled  in  the  earth,  absorb 


so  TRANSPLANTATION. 

the  juices  quicker  and  develop  their  foliage 
earlier  and  more  abundantly  than  those  moved 
in  the  spring ;  therefore  there  is  a  gain  of  time. 
From  these  considerations  it  may  be  more  cor- 
rect to  transplant  all  hardy  trees  and  those 
very  tenacious  of  life  in  the  autumn ;  imme- 
diately after  the  first  frost,  but  all  tender  trees  as 
Pears,  Peaches,  &c.,  it  is  safer  to  transplant  in 
the  spring.  Evergreens,  as  the  Fir,  Arbor  vitse, 
&c.,  are  better  moved  in  the  spring  also. 

With  respect  to  the  age  of  the  tree  when 
transplantation  should  take  place,  there  is  no 
doubt  that  young  trees  are  the  best  even  for 
immediate  beauty  and  effect.  In  moving  a 
large  tree  great  expense  and  care  are  requisite, 
and  even  then  it  is  probable  that  considerable 
pruning  must  take  place  to  restore  the  equili- 
brium between  the  roots  and  the  branches,  by 
which  operation  the  tree  remains  an  unsightly 
object  for  years,  and  probably  does  not  recover 
its  original  size  before  a  young  tree  would  pro- 
duce nearly  the  same  effect,  the  young  one 
remaining  a  beautiful  object  all  the  time. 

Therefore  except  in  cases  of  extremely  rare 
specimens,  it  is  better  to  abandon  the  idea  of 
transplanting  old  trees. 

Many  plants  of  Rhododendron  maximum  and 
Magnolia  glauca  are  annually  brought  in  the 


MANURES.  81 

spring  from  their  native  spots  in  this  vicinity 
for  sale ;  the  purchasers  generally  select  the 
largest  and  finest,  of  course  the  oldest  speci- 
mens, for  which  the  highest  price  is  paid.  They 
then  wonder  they  will  not  grow.  If  such  were 
planted  in  a  moist  shady  spot  and  headed  down 
they  might  have  a  fair  chance  of  surviving,  but 
younger  plants  would  be  far  preferable. 

Hardy  herbaceous  plants,  the  ornament  of 
the  open  garden  in  summer,  if  kept  in  pots  can 
be  transplanted  at  any  time  of  the  year.  The 
nursery  men  who  would  make  a  practice  of 
keeping  them  in  this  state,  would  sell  many  to 
their  summer  visiters,  who  are  delighted  with 
the  specimens  seen  in  flower,  but  afterwards 
forget  them. 

Manures. 

This  subject  is  difficult  to  reduce  to  the  few 
observations  permitted  by  the  size  of  this  work. 

The  purpose  of  manure  is  to  supply  those 
juices  and  gases  to  the  roots  of  plants,  of  which 
the  soil  has  been  exhausted  by  their  previous 
action  —  and  in  proportion  to  the  quantity  of 
this  supply  will  plants  acquire  luxuriance  or 
remain  weak.  Plants  differ  however  in  their 
capacity  of  thriving  on  manure.     Vines,  roses. 


82  MANURES. 

and  others  can  scarcely  ever  be  too  much 
manured  —  the  Pine  family  will  hardly  bear 
any  —  the  Cacti,  which  naturally  vegetate  on 
rocks  and  in  sand,  will  if  manured  attain  an 
excessive  vigorous  growth.  The  variety  of 
manures  and  their  useful  application  to  differ- 
ent plants  are  almost  infinite. 

Loamy  clay  absorbs  heat  slowly,  retains 
moisture  so  tenaciously  as  to  prevent  drain- 
age, and  is  so  compact  as  to  hinder  the  passage 
of  the  young  spongioles  of  the  root  through  it. 
Yet  mixed  with  a  large  quantity  of  sand,  peat, 
lime  and  manure,  it  becomes  valuable ;  its 
capability  of  retaining  moisture  enabling  it  to 
hold  the  solutions  of  the  peat,  lime,  and  manure 
until  gradually  used  by  the  roots,  which  valu- 
able solutions  would  quickly  run  through  a 
light  sandy  soil  without  clay,  before  the  roots 
had  time  to  absorb  them. 

Silex  or  the  component  part  of  sand,  when 
dissolved  by  the  potash,  soda,  or  other  alkaline 
properties  of  manure,  enters  into  the  tissue  of 
many  plants,  and  largely  into  all  grassy  plants  ; 
it  is  supposed  to  be  the  chief  cause  of  the  stiff- 
ness or  rigidity  of  the  stem  —  hence  it  is  valu- 
able as  a  manure ;  it  also  lightens  heavy  clayey 
soils.  Calcareous  earth  or  lime  also  enters  in 
appreciable  quantity   into  many  plants  in  the 


MANURES.  83 

shape  of  oxalate  or  phosphate  of  lime  —  bone 
manure   now  so  much   used  is    phosj)hate   of 
lime.     The  salts  of  potash  and  soda  are  like- 
wise   found   in   abundance    in    plants,   hence, 
besides  the  power  possessed  by  these  and  some 
other   salts   of    dissolving   various    substances 
found  in  the  earth  so  as  to  make  them  fit  juices 
for  absorption  by  roots,  they  themselves  are 
valuable  manures  in  the  shape  of  common  salt 
muriate  of  soda)  saltpetre,  (nitrate  of  potash) 
&c.,    but    they   should    be    applied    in    small 
quantities.     Ulmin  or  geine,  a  peculiar   sub- 
stance resulting  chiefly  from  vegetable  decom- 
position and  existing  in  abundance  in  peat  and 
in  common  manure,  has  lately  been  brought 
into   notoriety   in   the    Geological    reports    of 
different  States,  and  represented  as  the  essential 
part  of  manure,  without  a  supply  of  which  to 
vegetables  all  fruit  will  fail. 

Much  direct  experiment  is  still  wanting  to 
ascertain  the  true  value  and  operations  of  this 
substance.  The  small  knowledge  hitherto  pos- 
sessed on  the  subject  is  however  rather  in  favor 
of  the  theory. 

Those  who  consider  the  chemical  constituents 
of  a  soil  as  the  sole  tests  of  its  value  for  the  growth 
of  plants,  will  be  much  in  error  in  practice. 
Minerals  and  metals  or  rather  their  oxides 


84  MANURES. 

exist  in  plants  —  as  sulphur  in  the  cruciferous 
family,  particularly  in  mustard,  copper  in  coffee, 
wheat,  and  many  other  plants,  iron  in  tobacco, 
gold  in  the  sage,  &c.,  but  these  can  only  be 
taken  up  by  the  roots  as  solutions  of  their 
oxides,  nothing  solid  being  able  to  pass  through 
the  spongioles. 

Some  manures  sensibly  affect  the  colors  of 
flowers  as  is  well  known  to  the  tulip  growers, 
even  a  moderate  quantity  of  manure  spoils  all 
their  favorite  stripes.  The  change  of  the  pink 
color  of  Hydrangea  into  purple  is  probably 
produced  by  some  manure  containing  excess 
of  alkali. 

The  following  statement  of  the  strength  of 
manures  on  oats,  rye,  and  barley,  is  extracted 
by  Decandolle  from  Hermstadt  (Annalen  der 
Landwissenschaft,  Annals  of  Agriculture.) 

Sheeps  dung  on, 
Goats       " 
Horse      « 
Cow        " 
Human  fasces 
Pigeons  " 
Human  urine, 
Dry  bullocks  blood, 
Vegetable  earth, 
Unmanured  soil, 

These  trials  were  under  exactly  equal  cir- 
cumstances^ but  it  would  have  been  more 
satisfactory  had  the  experiment  been  tried  un- 


Rye. 

Barley. 

Oats. 

13  fold. 

16  fold. 

14  fold. 

13 

15 

15 

11 

13 

14 

9 

11 

16 

13 

13 

14i 

9 

10 

12 

13 

13 

]3 

14 

16 

m 

6 

7 

13 

4 

4 

5 

MANURES  85 

der  all  equal  circumstances  except  the  quality 
of  the  natural  soil,  which  should  have  varied  in 
particulars  of  composition,  tenacity,  silicious, 
calcareous  and  other  natural  admixtures. 

The  refuse  from  Sugar  Refineries  has  been 
considered  a  powerful  manure,  particularly 
from  those  where  animal  charcoal  or  burnt  and 
pulverized  bone  is  used  in  the  process  —  and 
this  refuse  has  been  carried  at  great  expense 
from  the  Refineries  at  St.  Petersburg  to  the 
South  of  France  for  the  purpose  of  manuring 
the  Vineyards.  It  consists  of  carbon  and  phos- 
phate of  lime  in  exceedingly  minute  division, 
also  of  vegetable  mucilage,  the  vegetable 
coloring  matter  of  sugar  which  is  probably 
carbon  in  another  state,  and  a  portion  of 
saccharine  juice. 

The  carbon  may  be  converted  into  carbonic 
acid  and  received  into  a  plant  for  the  purpose 
of  being  afterwards  decomposed  and  depositing 
its  carbon  there,  tlie  phosphate  of  lime  we 
know  from  the  action  of  bone  manure  is  very 
powerful,  and  in  this  case  is  so  very  finely 
divided  that  its  action  must  be  rapid.  Of  the 
effect  of  the  mucilage,  I  am  ignorant,  whether 
being  vegetable  it  is  capable  of  being  converted 
into  gcine  or  not,  but  I  suspect  not  as  it  re- 
8 


86  MANURES. 

sembles  the  substance  thrown  off  by  roots;  the 
saccharine  juice  is  in  sufficient  abundance  to 
create  the  strongest  fermentation  and  heat,  so 
much  so  that  the  boards  with  which  a  vessel 
was  lined  inside  while  carrying  a  cargo  of  this 
refuse  from  St.  Petersburg  to  Marseilles  were 
completely  converted  through  and  through  into 
charcoal.  There  is  no  doubt  therefore  that  it 
is  a  most  effective  manure,  but  it  requires 
great  caution  in  the  use,  and  to  be  mixed  with 
a  large  quantity  of  earth  previous  to  application, 
otherwise  its  heat  will  completely  destroy  vege- 
tation. One  injurious  effect  it  produced  how- 
ever was  to  excite  the  vines  so  excessively  that 
when  it  was  impossible  to  obtain  this  stimulus 
none  other  could  be  found  to  supply  its  place, 
and  the  vines  fell  into  a  state  of  weakness. 

It  has  lately  been  subjected  to  fermentation 
for  the  purpose  of  manufacturing  vinegar  from 
it  previous  to  its  application  to. the  soil.  This  of 
course  by  abstracting  the  saccharine  juice, 
leaving  a  portion  of  acetic  acid  in  the  mass, 
and  perhaps  by  destroying  in  some  measure 
the  phosphate  of  lime,  much  impairs  its  quality 
as  a  manure. 

On  the  much  discussed  question  of  the  com- 
parative value  of  manure  applied  fresh  from  the 
stable,  or  applied  after  it  has  lain  in  a  heap  for 


MANURES.  87 

some  months  and  fermented,  it  appears  that 
exposure  to  rain  dissolves  the  salts  it  contains, 
which  are  lost  by  washing  away,  and  the  heat 
of  fermentation  dissipates  the  gases  in  the 
atmosphere.  Both  these  are  of  value  to  the 
roots  of  plants. 

On  the  other  hand,  on  the  theory  of  Geine, 
the  fermentation  of  manure,  kept  in  a  heap,  de- 
composes the  vegetable  substance  and  converts 
it  into  geine,  which  is  thus  in  a  fit  state  for  imme- 
diate application  to  the  roots,  while  manure,  if 
spread  over  the  earth  in  a  fresh  state,  does  not 
heat  at  all  and  decomposes  very  slowly,  a  great 
proportion  of  the  gases  being  also  lost. 

The  application  of  liquid  manure  to  plants,  par- 
ticularly those  grown  in  pots  or  tubs,  is  consider- 
ably practised,  and  certainly  with  great  advan- 
tage. This  liquid  manure  is  usually  prepared 
hy  steeping  manure  in  water  and  drawing  it  off 
when  clear,  and  of  the  color  of  beer  or  porter. 
The  above  argument  applies  also  to  this  method. 

The  substances  found  in  plants  by  analysis 
are  by  no  means  true  tests  that  those  substances 
are  required  as  manure  to  make  them  flourish  ; 
thus  there  may  be  very  little  lime  found  in  a 
vegetable,  on  analysis,  and  yet  lime  as  phos- 
phate, (bone  manure)  carbonate,  (common 
8* 


88  MANURES. 

lime)  or  even  sulphate  (gypsum)  may  be  a 
useful  manure  for  that  vegetable  —  for  lime 
neutralizes  acids  which  may  be  found  in  the 
soil,  many  of  which  are  injurious ;  it  decom- 
poses and  prepares  various  other  substances,  as 
mucilage  or  gum  which  readily  dissolves  and 
alters  phosphate  of  lime,  thus  the  hurtful  exuda- 
tions of  roots  partly  possessing  this  mucilaginous 
nature  may  perhaps  thereby  be  rendered  inno- 
cuous or  useful,  &c.  There  is  indeed  perhaps 
as  much  or  more  yet  to  be  discovered  on  this 
subject  than  what  we  actually  know. 

Man  sows  and  cultivates  many  acres  of  the 
same  plant  together,  hence  arises  the  necessity 
of  manure  and  rotation.  Nature  mixes  all  her 
plants  in  varied  and  beautiful  profusion  — 
hence,  no  manure  or  rotation  is  necessary,  the 
exudations  of  the  roots  of  one  plant  become 
food  for  another,  and  the  same  plants  remain 
growing  on  the  same  spots  for  years,  nay  ages. 
Yet  when  nature  does,  as  in  the  case  of  forests, 
produce  the  same  tree  to  a  large  extent  —  the 
American  forests  teach  us  that  there  rotation 
also  becomes  necessary.  It  would  be  a  curious 
experiment  to  endeavor  to  ascertain  whether 
the  exudations  of  parasitical  plants  were  benefi- 
cial or  otherwise  to  the  trees  on  which  they  are 
said  to  feed. 


INDEX. 


The  numbers  re 

fer  to  the  pages. 

Acidity,  48. 

Fertility,  36. 

Adhesion,  9. 

Flavor,  48. 

Alburnum,  Id. 

Floral  envelopes,  34. 

Anther,  41. 

Flowers,  stunted  branches- 

Axil,  22. 

35. 

Flowers,  34. 

Bell  glasses,  69. 

double,  39. 

Buds,  26. 
Bulbs,  24. 

..^Tf^..^,-.^    on 

discoid  compound^ 

39. 
Fruit,  45. 

Calyx,  34. 

Cambium,  21. 

Flues,  64. 

Carbonic  acid,  32. 

Cells,  8. 

Germination,  55. 

Cellular  tissue,  2. 

Glass-houses,  63. 

Color,  61. 

Grafting,  73. 

Corolla,  34. 

Cuticle,  30. 

Heart-wood,  19. 

Cuttings,  68. 

Hybridising,  50. 

Darkness,  39. 

Inarching,  75. 

Insipidity,  49. 

Embryo,  51. 

Internodia,  19. 

Endogenous,  19. 

Evaporation,  64. 

Layers,  69. 

Evergreens,  80. 

Leaf-buds,  regnlar,  22. 

Excrementitious    matter, 

,  adventitious,.    22^ 

16. 

27. 

Exogenous,  19. 

Leaves,  29. 

Eyes,  26. 

Light  and  air,  60. 

90 


INDEX. 


Liber,  20. 

Manures,  81. 
Medullary  rays,  20. 

Nodi,  19. 
Nitrogen,  15. 

Ovula,  51. 

Petals,  4. 
Pistill,  41. 

Poisonous  gases,  64. 
Pollen,  41. 
Potted  plants,  78. 
Perspiration,  64. 

Root,  11. 

Rotation  of  crops,  16. 

Sap,  its  motion,  57. 

,  accumulation  of,  59. 

Sap-wood,  19. 
Scion,  25. 
Seed,  51. 
Sepals,  34. 


Seed-saving,  52,  56. 
Silver  grain,  20. 
Spiral  vessels,  9. 
Sport,  38. 
Spongioles,  11. 
Stamens,  41. 
Stem,  18. 
Sterility,  36,  59. 
Stigma,  42. 
Stock,  25.       ' 
Stomata,  11. 
Stoning,  40. 
Sweetness,  48. 

Tissue,  1. 
Training,  62. 
Transplantation,  77. 
Tubers,  11. 

Varieties,  38. 
Vascular  tissue,  8. 
Vivification,  42. 

Wood,  how  formed,  8. 
Woody  fibre,  8. 
Worn  out  soil,  16. 


p-a^ 


